Forming the comparative of some adjectives and adverbs.
[Old English suffix -ra (adjectival), -or (adverbial), of Germanic origin.]
The adjectives that make their comparatives with -er are generally those of one syllable: brighter, greater, harder, older, richer, tighter. Most of those with two syllables that end in -le, -er or -ow also add -er, as do those in -y or -ly (when the y changes to an i): simpler, cleverer, narrower, angrier, livelier. Most adjectives of two syllables or more form their comparatives with more instead.
A few adverbs are identical in form to the adjectives from which they derive, and follow the same rules for forming comparatives: he runs faster, I'll see you later. A few others, without corresponding adjectives, do the same: sooner, farther/further.
For the superlative form, see -est1.