Are there natural languages with the following properties (seen in Esperanto)?

Question

Are there natural languages that have the following set of properties:

• The language possesses nouns, adjectives, and definite articles
• Nouns and adjective are both inflected for number and case (or at least one of the categories) and show agreement
• The definite article is not inflected, but is invariable

This set of features is present in Esperanto:

la bela virino / la belaj vironoj / la belan virinon/ la belajn virinojn "the beautiful woman" / "the beautiful women" (Nom. Sg. /Nom. Pl. /Acc. Sg. /Acc. Pl.)

It is different from the behaviour of articles and adjectives in the standard average European languages: Either both articles and adjectives are inflected, or both aren't.

Answer 1

Generalising from fdb's answer about Arabic and postmortes' answer about Maltese: there are several languages in the Semitic family that have these three properties. Inflected nouns and adjectives are in Proto-Semitic, but definiteness was not a morphological category at that stage. However, some languages developed prefixes and suffixes for this purpose (Hebrew, Arabic, Aramaic, Amharic):

Definiteness seems not to have been a morphological category of Proto-Semitic. Akkadian does not indicate definiteness at all, and Ge'ez only in an incipient or covert way. In those languages which do have a definite article, the formal variation is striking. The article, though always affixal, is a prefix in some languages, a suffix in others. Thus Hebrew has the prefix ha-, Arabic has the prefix al-, whereas Aramaic uses the suffix -ā and South Arabian has the suffix -n. Amharic has innovated a new definite suffix -u from the old 3sg possessive clitic ‘his’ (see 2.). Nouns which have a pronominal possessive suffix, or which occur in the Construct form (and thus take a following dependent genitive), do not take the article. An indefinite article is found only in Arabic, where its suffixal form (nunation: -n) contrasts with the prefixal definite article al-, so that ‘definiteness’ is expressed in two different slots:

al-kitābu ‘the book’ vs. kitābu-n ‘a book’.

(Note that -n is an indefinite marker in Arabic, but a definite marker in South Arabian.)

^{Weninger, S., Watson, J. E., Streck, M. P., & Khan, G. (2011). The Semitic Languages: An International Handbook. Berlin: De Gruyter Mouton.}

Hence, it appears that the definite article has been a separate development in several branches of West Semitic (at least Arabian, North-West Semitic and Ethiosemitic). However, Amharic inflects the article so the non-inflected definite article seems to be restricted to Central Semitic.

Answer 2

• The language possesses nouns, adjectives, and a definite article
• Nouns and adjectives are both inflected for number and case and show agreement
• The definite article is not inflected, but is invariable for gender, number and case.

Arabic fits these criteria.

Answer 3

Welsh is another such language, to some extent at least.

Nouns and adjectives do not inflect for case; most nouns and a subset of adjectives inflect for number; the majority of adjectives do not inflect for number, though. All adjectives inflect for gender.

There is no indefinite article, but there is a definite article. The definite article has three different forms, but like English /ə ~ ən/ and /ðə ~ ði/, the forms are based on phonological environment, not morphological form:

• If the following word begins with a vowel sound (including /j/ and /h/, but not /w/), the article is yr
• If the following word begins with a consonant sound (including /w/), the article is y
• If the article follows a word that ends in a vowel sound, regardless of what the following begins with, the article is ’r

Using Wikipedia’s examples of the nouns bwrdd (m.) ‘table’ and bord (f.) ‘table’ with the inflecting adjective brwnt ‘dirty’:

    | m.                 |  f
-------------------------+--------------------
sg. | y bwrdd brwnt      | y ford front
pl. | y byrddau bryntion | y bordydd bryntion
----+--------------------+--------------------

Both bwrdd ~ byrddau, bord ~ bordydd, and brwnt/bront ~ bryntion/bryntion inflect for number here, but the article is uninflected. Apart from the regular gender inflection of adjectives modifying feminine nouns being subject to soft mutation, brwnt also has a specifically feminine form bront.

Answer 4

Maltese exhibits these properties (which you might have expected after @fdb's answer since Maltese is the "Arabic" European language).

The definite article in Maltese is il- and does not change according to number or gender. I can't quite claim that it's invariable as it changes to ic- in front of a c, ix- in front of an x and so on for the so-called sun letters, but to me at least that's a little like English choosing to use an before vowels and a otherwise.

Nouns and adjectives are inflected for both number and gender: the dog in Maltese is il-kelb and the dogs are il-klieb. (I was going to use cat -- qattus -- but then I'd have to explain how to pronounce that q). A big dog is il-kelb il-kbir and "big dogs" are il-klieb il-kbar. For many nouns there is also a third plural form into indicate there are exactly two of something

Answer 5

For typological questions you can consult related databases, such as The World Atlas of Language Structures (the most widely used), AUTOTYP, SSWL to get the answer. As mentioned, Arabic might be one such example.