Traditional grammars categorize determiners with either adjectives or pronouns. But determiners are not adjectives. Repeat after me: Determiners are not adjectives. Notional grammars define adjectives as “words that modify nouns.” (But not all words that modify nouns are adjectives.) Adjectives describe attributes of nouns, pronouns, and noun phrases, functioning as noun phrase modifiers, subject complements, and object complements. (Attributes are characteristics, features, or qualities.) Determiners provide non-attributive information such as definiteness, familiarity, location, quantity, and number about a nominal form, functioning as determinatives.
Both adjectives and determiners appear within noun phrases as dependents of the noun phrase head. For example, moist cake and the cake are both noun phrases. Moist is an adjective that describes the noun cake. The is a determiner, specifically a definite article, that provides information about the definiteness of the noun cake. Both moist and the appear directly before cake, but the adjective and determiner differ in grammatical form and grammatical function.
Grammatical Form
First, prototypical adjectives show three degrees of modification while determiners do not vary in internal structure. One can have a moist cake, a moister cake, or the moistest cake. The adjective moist has comparative and superlative forms. Determiners do not exhibit morphological change. One can say the cake but not *the-er cake or *the-est cake. Prototypical adjectives express comparative and superlative forms in addition to the positive form. Individual determiners are invariable in form.
- moist cake
- moister cake
- moistest cake
- the cake
- *the-er cake
- *more the cake
- *the-est cake
- *most the cake
Even absolute adjectives — adjectives that describe absolute states or conditions, or non-variable qualities that are not subject to qualification or limitation — can and do have comparative and superlative forms in English.
- The first woman is pregnant.
- The second woman is more pregnant.
- The third woman is most pregnant.
- Your plan is dead.
- That other plan is deader.
- That plan is the deadest plan.
Note that some determiners do appear to have comparative and superlative forms. For example, the determiner few is related to the determiners fewer and fewest, which diachronically and semantically are comparative and superlative forms. But the words few, fewer, and fewest are still determiners, giving non-attributive information about quantity rather than describing an attribute. Prototypical determiners do not have comparative and superlative forms.
Constituency
Second, determiners are always constituents of a noun phrase. Adjectives can function as complements, specifically subject complements and object complements. For example, the adjective blue in my house is bright blue functions as the subject complement. Blue is the head of the adjective phrase bright blue and is not a constituent of a noun phrase. Determiners cannot function as complements. *My house is the is grammatically impossible.
- My house is bright blue.
- *My house is the.
Within a noun phrase, determiners also always precede the phrase head as well as any modifiers. Adjectives can occur between a determiner and a noun. Although less common, an adjective can also follow a noun or pronoun. Up to three determiners and a p-word functioning as a particle can form a determiner phrase, but the determiner and/or determiner phrase also goes before the phrase head and before any modifiers.
- few big red apples
- *big few red apples
- *big red few apples
- few of the many big red apples
- *big few of the many red apples
- *big red few of the many apples
Word Classes
Third, determiners are a closed class, and adjectives are an open class. New words are added rarely, if ever, to closed classes. English has a finite number of determiners. New adjectives are added to the language frequently. For example, cromulent and bootylicious, are recent additions to the category of English adjectives. In contrast, the third person plural possessive determiner their is a more recent addition to the category of English determiners, entering the language from Old Norse around the thirteenth century.
Determiners are function words, and adjectives are content words. Determiners express little lexical meaning but express grammatical or structural relationships among other words. Adjectives express discernable lexical meanings. For example, the adjective big is easy to define as “not small, large.” On the other hand, the determiner the is more difficult to define in any way other than grammatical terms such as “a definite article.” (Note that lexical words and function words exist on the lexical-functional continuum. Some words express a combination of both lexical and functional features.)
Determiners Versus Pronouns
A final note on determiners versus pronouns. Some determiners are identical in form to related pronouns. For example, some possessive determiners in English are his, its, and whose. His, its, and whose are also forms of possessive pronouns. Compare the little girl is his child and the little girl is his. In the first sentence, his is a possessive determiner that provides information about the relationship to the noun child. In the second sentence, his is a possessive pronoun that takes the place of the noun phrase his child.
- The little girl is his child. (possessive determiner)
- The little girl is his. (possessive pronoun)
While two words can look the same, e.g., his and his, this and this, few and few, if two words differ in form and function, then the two words are two different words. Determiner his, this, and few are different words from pronoun his, this, and few.
Conclusion
To determine the syntactic category of a word, one must consider the form, function, and syntax of a word in comparison to other words and phrases. Determiners differ significantly from adjectives. Determiners are invariable in form; adjectives show three degrees of comparison. Determiners are always constituents of a noun phrase; adjectives can function as subject complements and object complements. Determiners are a closed class; adjectives are an open class. Therefore, determiners are not adjectives.
For more information, see English Determiners and English Adjectives.
This post was originally published on January 12, 2019 and updated on July 16, 2023.
References
Brinton, Laurel J. & Donna M. Brinton. 2010. The linguistic structure of Modern English, 2nd edn. Amsterdam: John Benjamins Publishing Company.
Hopper, Paul J. 1999. A short course in grammar. New York: W. W. Norton & Company.
Huddleston, Rodney. 1984. Introduction to the grammar of English. Cambridge: Cambridge University Press.
Kosur, Heather Marie. 2021. A Form-Function Description of the Grammar of the Modern English Language: Book 1 (Level 7). Rock Pickle Publishing.
Kosur, Heather Marie. 2021. A Form-Function Description of the Grammar of the Modern English Language: Book 1 (Level 8). Rock Pickle Publishing.