This article deals with denominations used to refer to human persons (personal nouns). In addition to the designations traditionally used for humans, a number of other nouns (also referring to inanimate referents) can, contextually or usually, be used as personal nouns. These items (such as 'tête', "head") generally have a grammatical gender that is maintained in the metonymic use, whether the word refers to a man or a woman. However, this gender is not always stable: In the past, a number of nouns designating a human by metonymy have become full personal nouns that can be used with both genders, like the majority of personal nouns. A similar evolution can be assumed for a number of other types of figurative use, for which attestations and a theoretical framework are provided to explain this movement.