An adverb qualifies a verb, adjective, participle, or sometimes another adverb, e.g. narrowly, never, transversely. It can give a more accurate or refined meaning to such a word when placed next to it, e.g. ‘grows commonly’, ‘narrowed abruptly’, ‘slightly scabrid’, ‘pungent, sometimes prominently’, ‘rarely minutely mucronate’. Many are formed from adjectives. In English, an adverb formed from an adjective is typically indicated by the ‘-ly’ ending. In Latin it is formed in several ways.

With adjectives of Group A you add -e to the stem, e.g. dense from densus to form ‘densely’, and with those of Group B you add -ter or -iter, e.g. prominenter from prominens to form ‘prominently’, irregulariter from irregularis, ‘irregularly’. Adverbs are not declined, nor do they change with gender or number.

Examples

minute hirsutus minutely hairy

foliis minute hirsutis with leaves minutely hairy

fructus lateraliter complanatus fruit laterally flattened.

Many words are adverbs in their own right. Some examples are saepe (often), mox (soon), saltem (at least), iterum (again, a second time), deinde (thereafter). Stearn has a list of Latin adverbs on pp 104–106.