- immediacy, immediateness, instantaneousness, instancy - the quickness of action or occurrence; "the immediacy of their response"; "the instancy of modern communication"
--1 is a kind of celerity, quickness, rapidity
- imperativeness, insistence, insistency, instancy - urgently demanding attention; "the insistence of their hunger"; "he pressed his demand with considerable instancy"
--2 is a kind of urgency