excuse-v; 2 Senses

Sense Number 1: Rationalize; make allowances for; accept.

Please excuse the mess.
Your good grades do not excuse your drinking.
You must excuse my husband, he doesn't speak English.

VerbNet: judgement-33
FrameNet: Forgiveness
PropBank: excuse.01
WordNet 3.0 Sense Numbers: 1, 3, 4, 6

Sense Number 2: Ask for permission to be released from an engagement or situation, perhaps as a courtesy.

NOTE: This is a subsense of sense 1 where the NP being excused is leaving a room or disappearing from an area. Syntax Is: NP1 EXCUSE NP2[human]

I asked the teacher if I could be excused to make a phone call.
Monroe had to be excused from the meeting for excessive coughing.
Excuse me!
"Excuse me, madame," he said.

VerbNet: NM
FrameNet: NM
PropBank: NM
WordNet 3.0 Sense Numbers: 2, 5