While adjectives and their potential universality have been much debated, adverbs remain rather neglected in the typological and cognitive literature. From a typological perspective, adjectives can be dealt with using a comparative concept: rather than assuming from the outset the existence of a class of adjectives, a particular language-independent definition of adjectives is used as a heuristic for examining recurrent form-meaning combinations. In the present article, adverb is addressed as a comparative concept in the same vein: an adverb is a lexeme that denotes a descriptive property and can be used to narrow the predication of a verb. This comparative concept is applied to a sample of 41 languages from the whole world. The results show that although there are diverse structural possibilities in terms of different adverbial constructions of varying spread and productivity, simple adverbs are found in a considerable number of unrelated languages, even in some cases where adjectives cannot be found. Clear adverb subtypes reminiscent of semantic types of adjectives further emerge, leading to a discussion of whether the comparative concepts in this case allow us to uncover a substantial cross-linguistic prototype.