Meronymy (from Greek μέρος meros, "part" and ὄνομα onoma, "name") is a semantic relation specific to linguistics, distinct from the similar meronomy. A meronym denotes a constituent part of, or a member of something. That is,
- “X” is a meronym of “Y” if Xs are parts of Y(s), or
- “X” is a meronym of “Y” if Xs are members of Y(s).
For example, finger is a meronym of hand because a finger is part of a hand. Similarly, wheels is a meronym of automobile.
Meronymy is the opposite of holonymy. A closely related concept is that of mereology, which specifically deals with part-whole relations and is used in logic. It is formally expressed in terms of first-order logic. A meronymy can also be considered a partial order.
A meronym refers to a part of a whole. A word denoting a subset of what another word denotes is a hyponym.
In knowledge representation languages, meronymy is often expressed as "part-of".