excuse

nouns

a defense of some offensive behavior or some failure to keep a promise etc.
"he kept finding excuses to stay"; "every day he had a new alibi for not getting a job"; "his transparent self-justification was unacceptable"
alibi, exculpation, excuse, self-justification
a note explaining an absence
"he had to get his mother to write an excuse for him"
excuse
is a type of (narrower)
a short personal letter
"drop me a line when you get there"
billet, line, note, short letter
a poor example
"it was an apology for a meal"; "a poor excuse for an automobile"
apology, excuse

verbs

accept an excuse for
"Please excuse my dirty hands"
excuse, pardon
grant exemption or release to
"Please excuse me from this class"
excuse, exempt, let off, relieve
serve as a reason or cause or justification of
"Your need to sleep late does not excuse your late arrival at work"; "Her recent divorce may explain her reluctance to date again"
excuse, explain
defend, explain, clear away, or make excuses for by reasoning
"rationalize the child's seemingly crazy behavior"; "he rationalized his lack of success"
apologise, apologize, excuse, justify, rationalise, rationalize
is derived from
excusatory
ask for permission to be released from an engagement
beg off, excuse
excuse, overlook, or make allowances for; be lenient with
"excuse someone's behavior"; "She condoned her husband's occasional infidelities"
condone, excuse
is derived from
excuser