The Standard Definition of an Adjective
The simplest way to define an adjective is to say that an adjective is a word that describes something. An example of an adjective is the word green in the phrase “the green grass.” An adjective can give many kinds of information about a noun, such as its color, size, and shape.
To think of adjectives simply as “describing words,” however, can lead people to misidentify an adverb or a determiner as an adjective. The purpose of this article is to show you how to accurately identify which descriptive words are adjectives and which ones are not.
A distinguishing feature of adjectives is that they can describe only nouns and not words from any other word class. To illustrate, I have included two examples below, both of which use the descriptive word late
Adjective: Jim was late for the meeting.
In this sentence, late is an adjective because it is used to describe Jim, which is a proper noun.
Adverb: Jim arrived late to the meeting.
In this second example, late isn’t telling us directly about Jim. Instead, it is telling us about the way he arrived somewhere. Because arrive is a verb, late is an adverb in this example.
If a descriptive word (e.g., late) describes a verb rather than a noun, it is not an adjective. It is an adverb.
If you know the difference between nouns and verbs, you can differentiate between adjectives and adverbs. However, it is not so straightforward to differentiate adjectives from determiners. This is because determiners, like adjectives, can be used to describe nouns. For example, the word two in the sentence “Two birds flew overhead” describes to us something about the noun birds.
So why isn’t two an adjective if it describes a noun? The answer is not exactly straightforward. Understanding why two is not an adjective requires a relatively deep understanding of what makes an adjective an adjective, which is covered in the following section.
The Characteristics of Adjectives
The word two is not an adjective in the phrase “two birds” because it does not have the characteristics of an adjective.
Most adjectives can (i) build off of each other, (ii) be intensified by words like very, and (iii) be written in a comparative or superlative form to make comparisons.
Adjectives build off each other indefinitely before the noun is introduced.
We can use a single adjective to give a simple description of something.
He drives a small car.
We can add more adjectives as we please to give more description. To the example above, the adjective new can be inserted, either in front of the word small or after it.
He drives a new, small car
He drives a small, new car.
Countless other adjectives can be inserted without resulting in an ungrammatical sentence.
He drives a small, new, clean, shiny, comfortable, speedy car.
Now, what happens when we try to insert the word two? Our first indicator that two is not an adjective is that it can be placed only in front of a list of adjectives, not within it and not after it.
Correct: He drives two small, new, clean, shiny, comfortable, speedy cars.
Incorrect: He drives small, new, clean, two, shiny, comfortable, speedy cars.
(Most) adjectives can be intensified by words such as really and too.
The word two does not meet this requirement, either.
Correct: He drives a very new car.
Correct: He drives a remarkably clean car.
Incorrect: He drives really two cars.
The word two would need to come before the intensifier if there are adjectives in the phrase.
He drives two really small, new cars.
This isolates two from the adjectives, further solidifying its role as a determiner rather than an adjective.
Absolute adjectives
Note that some adjectives lack this characteristic. However, this is not because it breaks the rules of English grammar. Certain adjectives–called absolute adjectives–just don’t make sense if they are intensified. An example of an absolute adjective is stolen. Either something is stolen, or it isn’t, and no one would ever say that something of theirs was “very stolen” from them. Therefore, even though such words lack this characteristic of adjectives, they are still classified as adjectives.
To reinforce this idea, notice how, unlike two, stolen gets placed after the intensifier — not before it — if it is part of a list of adjectives.
Correct: He drives a really small, new, stolen car.”
(Most) adjectives can take plain, comparative, and superlative forms.
In other words, adjectives can take the suffixes -er and –est, or they can have the words more and most placed in front of them. (Absolute adjectives are again an exception.)
Correct: He drives a newer car than I do.
Correct: He drives the most comfortable car I’ve ever been in.
The word two does not have this characteristic because nothing can have more “two-ness” than something else.
Incorrect: He drives twoer cars than I do.
Incorrect: He drives more two cars than I do.
Reference:
Aarts, B. (2011). Oxford modern English grammar. New York, NY: Oxford University Press.