Wiktionary
a. That has not been excused
WordNet
adj. not excused; "too many unexcused absences"
Usage examples of "unexcused".
I might have been a child facing the school principal over a series of unexcused absences.
Frank Allen had also called to say that Bobby had had an unexcused absence a week earlier.
Three unexcused or unexplained absences will be grounds for immediate termination of your contract.
Alys was not artistic like Charles, but she had one talent which made her the envy of all her friends, especially those friends who had frequent unexcused absences at school.
I waited around the front office for a few minutes, watching the kids come in to whine about tardy slips and unexcused absences, then followed a no-nonsense rump into the shrine for a word with the principal.
Do you realize certain violations and a number of unexcused absences from school can keep you from getting your license in Georgia?
Charlie in a particularly foul mood, it was an unexcused absence by one of his dancers.