Gram. 1. perfect with respect to a temporal point of reference in time to come; completed with respect to a time in the future, esp. when incomplete with respect to the present.
2. noting or pertaining to a tense or other verb formation or construction with such reference.
3. the future perfect tense.
4. another verb formation or construction with future perfect meaning.
5. a form in the future perfect, as He will have come.