Languages

Russian support

Russian (ru) accepts both international symbols such as kg, W, and Hz and standard Cyrillic symbols such as кг, Вт, and Гц. These aliases resolve to the same canonical unit identities, so 5 кг expands to 5 килограмм and 100 Вт expands to 100 ватт. Unit output remains a canonical singular lemma; Russian plural, case, and numeral-government inflection is handled outside abbr2words. Ambiguous one-letter abbreviations such as г. and р. remain unchanged unless a future context mechanism can disambiguate them.

Vietnamese (vi) remains in the reviewed baseline tier. Its source-backed rules expand guarded TP., ĐT, SĐT, and academic-title forms, while legal identifiers and ambiguous uppercase tokens remain unchanged. The common-unit inventory has 38 identity entries and now exposes 38 localized spoken labels; the separate numeric currency identity VND/₫ is currency-vietnamese-dong. Coverage reports distinguish unit identities from localized labels.

English, French, Italian, Portuguese, and Spanish structured quantities recognize the reviewed shared currency identities €/EUR, $/USD, and £/GBP in either numeric-prefix or numeric-suffix position. Portuguese additionally recognizes R$/BRL as currency-brazilian-real, while Czech recognizes Kč/CZK as currency-czech-koruna. These matches preserve the written numeric lexeme, source offsets, written symbol, language, category, and stable canonical ID; they do not speak the amount or choose locale-specific currency grammar. Downstream consumers such as spokenform own that semantic realization.

French dotted duration forms min. and sec. are context-sensitive structured quantity aliases. A numeric match consumes the complete dotted symbol, while standalone lexical min. continues to expand as minimum; numeric context is what selects the duration identity. Sentence punctuation is rendered by the generic abbreviation layer, and French number grammar remains downstream.

German quantity symbols include the reviewed electrical and frequency forms kWh, Wh, mAh, mA, GHz, MHz, kHz, Hz, W, and V, plus Stck., ltr., Tsd., Mio., Mrd., and EUR. Case-sensitive metadata is preserved: for example, 2 mA matches but 2 ma does not. Dotted German aliases and their base symbols share canonical IDs, so h/Std., min/Min., and l/Ltr. cannot acquire separate semantic identities.

German lexical coverage includes the reviewed common forms vgl., i.d.R., o.ä., and u.U., including narrowly spaced-dot aliases such as i. d. R.. For example,

vgl. Abschnitt 2; i.d.R. gilt das, u.U. auch für Geräte o.ä.

abbr2words owns the lexical abbreviation expansion. Brand, foreign-word, and model-specific pronunciation remains downstream.

Japanese support

Japanese (ja) keeps unknown initialisms disabled and uses source-backed, structural rules. № 12 expands to 番号 12; parenthesized or compatibility organization forms such as （株）, (有), ㈱, and ㈲ expand to their full company names. Bare kanji such as 番, 株, and 有 remain unchanged, as do ordinary forms such as 一番, 13番10号, and 頁 12.

The shared 38-unit inventory has Japanese labels. CLDR-style quantity templates render 20°C as 摂氏 20 度 and 80 km/h as 時速 80 キロメートル. This is a reviewed baseline and source-backed registry, not a claim of complete native-speaker review.

Arabic support

Arabic (ar) provides a source-backed conservative baseline with localized labels for all 38 shared common-unit identities. It expands د. and guarded م. titles, numeric page references such as ص. and ص, and numeric Gregorian, Hijri, and BC markers such as م, هـ, and ق.م. Arabic output preserves source number characters and does not perform number agreement, case, gender, dialect selection, or region-specific currency or academic-rank expansion.

Thai support

Thai (th) provides a source-backed conservative baseline for professional and academic titles, Buddhist and Gregorian eras, date-guarded month abbreviations, and clock-time markers. Common Latin/SI symbols and Thai short forms such as ม. and กม. resolve to Thai unit labels only with numeric quantity evidence. For example:

from abbr2words import abbr2words

assert abbr2words("ระยะ 5 กม.", lang="th") == "ระยะ 5 กิโลเมตร"
assert abbr2words("27 ส.ค. 2569", lang="th") == "27 สิงหาคม 2569"

Ambiguous forms such as ม.เชียงใหม่ remain unchanged because ม. is also the Thai meter symbol. Broader address, administrative, and institution abbreviation coverage still requires native review.

Mandarin Chinese support

Mainland Chinese (zh_CN) is a separate Simplified-Mandarin locale overlay. It localizes the common unit inventory, uses explicit ASCII-token boundaries so reviewed Latin abbreviations can touch Han characters, and expands only the reviewed semantic terms by default. Unknown uppercase identifiers remain unchanged. The zh_HK and zh_TW overlays remain separate and do not implicitly inherit Mainland terminology.

Known ambiguity

Some inventories contain collisions whose effective winner follows the source registry order rather than a complete contextual model. Current documented examples include str. in Czech, mar. in Spanish and Italian, n° in French, and seg. in Portuguese. German Fr. has an explicit title-context override, but its default expansion remains Freitag.

Context policy is language-specific and uses bounded local windows. English profiles distinguish street suffixes, saints, titles, and addresses; the German profile distinguishes Fr. Müller (Frau) from Am Fr. (Freitag). Name evidence uses Unicode cased characters and supports accents, apostrophes, hyphens, and quoted names. Uncased scripts remain conservative without an annotation signal. Context-aware output is still not a comprehensive semantic disambiguator, so applications should review domain-specific entries.

Uppercase undotted initialisms such as English time zones, BCE, CE, and MIT are case-sensitive. This prevents ordinary lowercase words from being rewritten; reviewed title-case and lexical abbreviations retain their own registry policy.

Coverage tiers and generated inventory

Coverage metadata is checked in with the language bundles and registry shards. Run python scripts/generate_registry_snapshot.py after an intentional data change and inspect the shard diff.

The detailed generated count table is maintained in docs/language-coverage.md.

Baseline unit labels are neutral surface labels, not plural/case/gender or numeral-government realization. Consumers that need semantic quantities should use iter_unit_matches() and perform locale grammar downstream.

DATE requires nearby numeric date evidence and is deliberately not an unrestricted parser. Uncased scripts remain conservative without the cased letter title heuristic; CJK entries do not rely on Latin \b behavior.