1) Part to whole relation 2) Semantic relation 
Meronymy (from Greek μέρος meros, `part` and ὄνομα onoma, `name`) is a semantic relation used in linguistics. A meronym denotes a constituent part of, or a member of something. That is, For example, `finger` is a meronym of `hand` because a finger is part of a hand. Similarly, `wheels` is a meronym of `automobile`. Meronymy ...
[n] - the semantic relation that holds between a part and the whole
part to whole relation noun the semantic relation that holds between a part and the whole