A verb is a word that carries some kind of action. Latin verbs are inflected according to their mode, tense, voice, number, and person, although there are several types of inflection tables that restrict these attributes.
For the vast majority of verbs in a Latin dictionary, each term might inflect into several other inflectable words: participles, gerunds, and supines.
Altogether these considerations make the verb easily the most complex type of word in the Latin langugage.