Not present and not excused, for short

AWOL

Think of a military term for someone who's missing without permission, often used when a soldier leaves their post unexpectedly.

This clue plays on the military term "AWOL," which stands for "Absent Without Official Leave." The phrase "not present and not excused" directly describes someone missing without permission, while "for short" hints at the acronym. It’s a straightforward definition with no hidden wordplay—just a common abbreviation for an unauthorized absence.