"Is a part" refers to being a component or an element of something. There are various synonyms that can be used to convey a similar meaning. For instance, "is an ingredient" denotes that something is necessary for the whole to function properly. "Is a segment" implies that something is a smaller piece of a larger whole. "Is a constituent" emphasizes that something is an essential part of an entity. "Is a fragment" signifies that something is a broken piece of the whole. "Is a section" suggests that something belongs to a particular part of the whole. Thus, these synonyms help to convey the concept of being a part of something with different nuances.