ADJECTIVE.
An Adjective is a word joined to a Substantive to express its Quality[15].
In English the Adjective is not varied on account of Gender, Number, or Case. The only variation it admits of is that of the Degrees of Comparison.
Qualities admit of more and less, or of different degrees: and the words that express Qualities have accordingly proper forms to express different degrees. When a Quality is simply expressed, without any relation to the same in a different degree, it is called the Positive; as, wise, great. When it is expressed with augmentation, or with reference to a less degree of the same, it is called the Comparative; as, wiser, greater. When it is expressed as being in the highest degree of all, it is called the Superlative; as, wisest, greatest.
So that the simple word, or Positive, becomes Comparative by adding r or er; and Superlative by adding st, or est, to the end of it. And the Adverbs more and most placed before the Adjective have the same effect; as, wise, more wise, most wise[16].
Monosyllables, for the most part, are compared by er and est; and Dissyllables by more and most: as, mild, milder, mildest; frugal, more frugal, most frugal. Dissyllables ending in y easily admit of er and est; as happy, lovely. Words of more than two syllables hardly ever admit of er and est.
In some few words the Superlative is formed by adding the Adverb most to the end of them: as, nethermost, uttermost, or utmost, undermost, uppermost, foremost.
In English, as in most languages, there are some words of very common use that are irregular in this respect: as, good, better, best; bad, worse, worst; little, less[17], least; much, or many, more, most; and a few others.