In linguistics, an agent noun (in Latin, nomen agentis) is a word that is derived from another word denoting an action, and that identifies an entity that does that action.[1] For example, driver is an agent noun formed from the verb drive.[2]
Usually, derived in the above definition has the strict sense attached to it in morphology, that is the derivation takes as an input a lexeme (an abstract unit of morphological analysis) and produces a new lexeme. However, the classification of morphemes into derivational morphemes (see word formation) and inflectional ones is not generally a straightforward theoretical question, and different authors can make different decisions as to the general theoretical principles of the classification as well as to the actual classification of morphemes presented in a grammar of some language (for example, of the agent noun-forming morpheme).