As a group during the FHIR Connectathon's Terminology track, we all agreed that ValueSet.compose should be renamed to ValueSet.definition. Although the ValueSet resource has a high maturity, we feel it should be changed now, while it can (before it becomes normative).

The use of the term "compose" is misleading, when there is also an operation called $compose. What ValueSet.compose really represents is the "definition" of the value set, as stated in the description of the element ("the definition of the content of the value set").