Guide · Annotation

Arabic NER Annotation: Guidelines for Entities, Spans & Edge Cases

Deciding what counts as an entity is the easy part. Deciding where it starts and ends is not. The span rules, name rules and taxonomy choices to write down before labeling, with worked Arabic examples and a verified dataset table.

Bayanat Labs Research· · 11 min read

Arabic NER annotation means marking the names of people, places, organizations and other entities in Arabic text, with a type and exact span boundaries. It is harder than in English for three reasons: Arabic has no capital letters, conjunctions and prepositions attach directly to names, and many given names are also ordinary adjectives. A usable Arabic NER guideline therefore fixes span rules for clitics, the article and titles, defines how to handle names that double as common words, and picks a published entity scheme before anyone labels.

Below: span rules with worked examples, Arabic name structure, sector taxonomies and a dataset table checked against the papers. For tokenization, normalization and tool setup, see our playbook on how to annotate Arabic text.

Why is Arabic named entity recognition hard?

Khaled Shaalan's survey of Arabic NER (Computational Linguistics, 2014) lists the causes. Four shape the guideline:

  • No capitalization. Arabic script has none, and the survey notes that most Arabic proper nouns look exactly like common nouns or adjectives.
  • Agglutination. Conjunctions (و، ف) and prepositions (ب، ل، ك) attach to the name, so one entity has many surface strings.
  • Missing short vowels. Unvoweled قطر can be Qaṭar, the country, or quṭr, "diameter"; only context decides.
  • Spelling variation. Foreign names are transliterated many ways; the survey's example is "Washington".

Leave any of these undecided and every annotator decides differently.

Arabic NER span rules: clitics, the article, titles and nesting

Two conventions are defensible. Word-level spans cover whole whitespace tokens. Wojood (Jarrar et al., LREC 2022) works this way: attached prefixes and suffixes count as part of the entity name. Clitic-excluded character spans start after attached conjunctions and prepositions. The difference is portability: clitic-excluded spans can always be widened to whole words, while word-level spans need a morphological segmenter to narrow them. This guide recommends clitic-excluded character spans, with the definite article ال kept inside the span because it is part of the name as written.

TextCorrect (clitic-excluded)Common errorRule
وبالرياض wa-bi-r-Riyāḍ, "and in Riyadh"Span الرياض (GPE); و and ب outsideSpan رياض: the article is droppedStrip proclitics, keep ال
للرياض li-r-Riyāḍ, "to Riyadh"Span لرياض (GPE) with canonical form الرياض in an attributeTyping الرياض into the span, which is not in the textSpans quote the text; canonical forms go in attributes
منظمة الأمم المتحدة munaẓẓamat al-Umam al-Muttaḥida, "the United Nations Organization"Span منظمة الأمم المتحدة (ORG)Including منظمة on some items and excluding it on othersOne rule for descriptor words; CLEANANERCorp includes them
الدكتور محمد ad-duktūr Muḥammad, "Dr. Muhammad"محمد (PERS); الدكتور as OCC if your scheme has itOne PERS span over the title and nameTitles sit outside person spans
مدير بنك القاهرة mudīr Bank al-Qāhira, "the Bank of Cairo manager"OCC over all three words, containing ORG بنك القاهرة, containing GPE القاهرةA flat ORG only, which loses the role and the cityIn nested schemes, annotate every layer
حرب عام 1973 ḥarb ʿām 1973, "the 1973 war"Span over all three words (EVENT)EVENT on حرب aloneWojood includes an event's date and place in its name
وعاصمتها wa-ʿāṣimatuhā, "and its capital"No entityTagging it as a locationA cue word points to an entity; it is not one

The title, nesting and event rows follow Wojood's guidelines: person names exclude titles (except prophets, kings and similar), occupations get their own OCC type, and the Bank of Cairo manager is the paper's own nesting example. The descriptor row follows CLEANANERCorp (Al-Duwais, Al-Khalifa and Al-Salman, OSACT 2024), whose MUC-based re-annotation of ANERcorp includes words such as منظمة and شركة in organization names. The Arabic annotation guidelines template has a slot for each of these rules.

Names that are also ordinary words

Shaalan's classic case is أشرف: the name Ashraf, the verb ashrafa, "he supervised", or the superlative ashraf, "most honorable". Many more are everyday words:

WordAs a nameAs an ordinary wordContext that decides
حسنḤasan (PERS)ḥasan, "good"أداء حسن "good performance" vs قال حسن "Hasan said"
كريمKarīm (PERS)karīm, "generous"رجل كريم "a generous man" vs اتصل كريم "Karim called"
أملAmal (PERS)amal, "hope"Agreement: a following feminine verb or pronoun often signals the person
جدةJidda, Jeddah (GPE)jadda, "grandmother"Location cues such as في or مسقط رأسه "his birthplace"
قطرQaṭar (GPE)quṭr, "diameter"Measurement vocabulary vs political or travel context

Four rules:

  1. Tag function, not form. A word is an entity only when it names a specific referent here. A gazetteer hit is a hint, not a label.
  2. Write the cue words down. Titles (السيد، الشيخ، الأستاذة), kinship particles (بن، أبو) and place cues (مسقط رأسه) do the work capital letters do in English; Shaalan calls them trigger words.
  3. Allow an "ambiguous" flag rather than forcing a guess. CLEANANERCorp reports that the first words of many ANERcorp sentences had no clear correct label.
  4. Seed gold items with homonyms, the same word as a name and as an adjective, to measure this confusion directly.

How Arabic names are structured, and where the span ends

The IFLA guide to Arabic personal names (2018) sets out the traditional name elements used below; the example names are common, widely attested ones.

ElementWhat it isExampleNER rule
IsmGiven name, often compound: عبد plus one of the names of Godمحمد, عبد الرحمنNever split: عبد الرحمن is B-PERS I-PERS; joined عبدالرحمن is the same name
NasabPatronymic with ابن / بن "son of" or بنت "daughter of"ابن حزمInside the person span, particle included
Kunyaأبو "father of" or أم "mother of" plus a child's nameأبو بكرPERS even when used alone to refer to a person; but أبوظبي (Abu Dhabi) is a GPE
LaqabEpithet or honorific, including compounds with الدينالصديق, نور الدينInside the span when part of the name; not an occupational title
NisbaAdjective of origin, tribe or affiliation ending in ـيالبغدادي, التميميInside the span as a surname; the same adjective after a common noun is not a person

The nisba row hides a common confusion. In الوفد السعودي (al-wafd as-Saʿūdī, "the Saudi delegation"), السعودي is a nationality adjective. It is not a surname and belongs in NORP if your scheme follows OntoNotes. Modern names rarely carry all five elements, and usage differs by country, so take guideline examples from your own data, not classical texts.

Entity taxonomies for finance, government and healthcare

The AMWAL authors (Abdo, Hatekar and Cavar, FinNLP 2025) note that most Arabic NER systems remain generic, medicine aside. Start from a published base; add only what your product uses:

SectorStart fromHard cases to write rules for
Finance and bankingAMWAL's 20 types, adopted from the Financial Industry Business Ontology (FIBO) and extended: CORPORATION, BANK, STOCK EXCHANGE, FINANCIAL INSTRUMENT, CURRENCY, METRIC and othersOne company, several names: AMWAL cites أوراسكوم, the full legal name and شركة أوراسكوم. Link them to one canonical ID.
Government and public sectorWojood's 21 types, which include LAW, OCC, DATE and MONEY, plus WojoodFine's 31 ACE-compatible subtypes of GPE, LOC, ORG and FAC (for example COUNTRY, STATE-OR-PROVINCE and TOWN)Ministries versus ministers (nested ORG inside OCC), and legal references: Wojood's guideline lists المادة (114) من قانون العقوبات "Article 114 of the Penal Code" as a LAW example. Decide whether article numbers are part of the span.
HealthcareYour own clinical vocabularies. An illustrative starting set: DISEASE, SYMPTOM, DRUG, DOSE, PROCEDURE, ANATOMYLatin-script drug names and English abbreviations inside Arabic sentences; patient identifiers need a PII layer and in-region handling (see our PDPL and data residency checklist).

Domain types need domain annotators: a banker knows a sukuk is an instrument; a physician knows which abbreviation is a drug.

Arabic named entity recognition datasets

Figures are as reported by each paper or dataset page (as of September 2026):

DatasetTextSizeEntity typesNotes
ANERcorp (Benajiba et al., 2007)News, MSACAMeL Lab split: 125,102 training and 25,008 test wordsPER, LOC, ORG, MISCStandard benchmark; agreed split from 2020; CC BY-SA 4.0
CLEANANERCorp (2024)ANERcorp, re-annotated9,518 label corrections, about 6.34% of the dataPER, LOC, ORG, MISCFixes inconsistent, wrong and missing labels; on GitHub
AQMAR (Mohit et al., EACL 2012)Arabic Wikipedia74,000 tokens, 28 articlesHand-annotated named entitiesSmall, but encyclopedic rather than news
Wojood (Jarrar et al., LREC 2022)MSA web and archive text, plus about 65K tokens of Palestinian and Lebanese dialect textAbout 550K tokens, about 75K entities, 22.5% nested21 typesNested; available on request for academic and commercial use
WojoodFine (Liqreina et al., 2023)WojoodAbout 44K mentions given subtypesWojood types plus 31 subtypesACE-compatible; used in the WojoodNER 2024 shared task
AMWAL (2025)Three Arabic financial newspapers, 2000–202317,185 entities20 financial typesSemi-automatic, manually reviewed; spaCy files on GitHub
ANERD (Alotaibi and Menai, 2026)Mixed Arabic sources (see the accompanying paper)502,756 sentences, about 11.6M tokensPERS, ORG, LOC, MISCAdds entity linking to Arabic Wikipedia; annotations under CC BY 4.0

Two cautions. ANERcorp scores across papers are hard to compare: the CAMeL Lab page explains that copies drifted between users until the agreed 2020 split. And none of these corpora is your domain. Use public data to pre-train and choose a scheme; build the test set from the text your model will see, in every dialect you serve (see why dialect coverage sets your model's ceiling).

How do you QA Arabic NER annotation?

Wojood and CLEANANERCorp both document reusable quality processes.

  • Screen on hard items. Wojood gave about 30 trained candidates a deliberately hard 750-token quiz and recruited the 12 who scored above 90%.
  • Review by entity list, not only by sentence. Wojood's experts reviewed a list of every annotated entity, which exposes one string carrying different labels. CLEANANERCorp found exactly that in ANERcorp: الضفة الغربية (aḍ-Ḍiffa al-Gharbiyya, "the West Bank") was tagged LOC in some sentences and O in others.
  • Let a model flag, and people decide. Wojood retrained a tagger on its own labels and had annotators check every mismatch, twice. CLEANANERCorp ran confident learning (the cleanlab library), which flagged 1,945 issues for manual review.
  • Measure agreement the NER way. The Wojood paper notes that Cohen's kappa can overstate NER agreement because most tokens are O. Report pairwise span-level F1 per type, and separate boundary disagreements from type disagreements; they have different fixes.
  • Test pre-labels before trusting them. In LabelBench, a different task, a local language model scored 78% on binary Arabic toxicity. On the real multi-label taxonomy, its exact-match accuracy on the fixed held-out manifest fell to 25.3%. Measure any pre-labeler on your own gold first.

Bayanat Labs follows a Vet, Train, Produce, QA, Deliver method. Contributors, including licensed professionals for financial, legal and medical text, pass dialect and domain screening before touching client data; work is calibrated against gold standards with adjudication, rework and an audit trail. Our Arabic data annotation services include NER and span labeling across 25+ Arabic varieties, hosted in-region by default.

Key takeaways
  • Decide boundaries first. Write rules for clitics, ال, descriptors, titles and nesting.
  • Prefer clitic-excluded character spans. They widen to word spans later; the reverse needs a segmenter.
  • Tag function, not form. حسن، كريم، جدة are names only in context; seed homonyms into gold.
  • Know the name elements. Ism, nasab, kunya, laqab and nisba belong inside the person span; nationality adjectives and occupational titles do not.
  • Borrow tested schemes and QA. Start from Wojood, WojoodFine or AMWAL; review entity lists and report span-level F1.

Frequently asked questions

What entity types should an Arabic NER dataset use?

Start from a published scheme so your data stays comparable. Use the four CoNLL-style types (person, location, organization, miscellaneous) if you need to compare against ANERcorp. Use Wojood's 21 OntoNotes-compatible types if you need dates, money, laws, occupations or nesting. Then add only the domain types your product actually consumes, such as financial instruments or drug names, and write three Arabic examples and one counter-example for each.

Can Wojood be used for commercial projects?

The SinaLab repository states that the full Wojood corpus is available on request for academic and commercial use, and that the annotation guidelines are available by emailing Prof. Jarrar. Read the terms before training a production model. ANERcorp, by contrast, is distributed by CAMeL Lab under CC BY-SA 4.0, whose share-alike clause matters if you redistribute derived data.

What is the difference between flat and nested Arabic NER?

Flat NER gives each token at most one entity label. Nested NER allows an entity inside another: in Wojood's example, the phrase for "Bank of Cairo manager" is an occupation that contains an organization, which contains a city. Nesting keeps more structure for search and knowledge graphs but is slower to annotate. Nested labels can later be collapsed to the outermost layer.

Is ANERcorp still a good benchmark for Arabic NER?

It is still the standard point of comparison, but read results with care. It is news text with four entity types. Before 2020, papers used different copies and splits, so scores are not directly comparable. The 2024 CLEANANERCorp study also found and corrected label errors in it. Report which version you used, and test on your own domain before trusting any score.

Do dialectal Arabic texts need different NER guidelines?

The entity types can stay the same; the rules around them need additions. Dialect and social media text brings unstable spellings of the same name, Latin-script and Arabizi names, nicknames and different cue words. Wojood includes about 65K tokens of Palestinian and Lebanese dialect text, collected from social media and other Levantine sources, for this reason. Add dialect-specific examples to each rule, and route dialect items to annotators who speak that variety.

Need an Arabic NER guideline tested on your data?

Bayanat Labs runs a fixed-scope pilot with gold-standard QA and a quality report, usually within two weeks. Annotators are screened on the dialect and domain they label, with adjudication and an audit trail on every task.

Scope a pilot