unpunctual

adjective

1. strictly observant of an appointed or regular time; not late; prompt.
2. made, occurring, etc., at the scheduled or proper time: punctual payment.
3. pertaining to or of the nature of a point.
4. punctilious.

adjective

1. arriving or taking place at an arranged time; prompt
2. (of a person) having the characteristic of always keeping to arranged times, as for appointments, meetings, etc
3. obsolete precise; exact; apposite
4. maths consisting of or confined to a point in space

adj.1740, from un- (1) “not” + punctual. adj.c.1400, from Medieval Latin punctualis, from Latin punctus “a pricking” (see point (n.)). Originally “having a sharp point; of the nature of a point;” meaning “prompt” first recorded 1670s, from notion of “insisting on fine points.” Related: Punctually.