blot copybook

blot your copybook

(British & Australian)

to do something which spoils someone's opinion of you She blotted her copybook by arriving late to a meeting.

Name	Pronounced	Usage
Radomir	-	Serbian, Russian, Bulgarian, Medieval Slavic
Innes	-	Scottish
Brutus	-	Ancient Roman
Craig	[kreig]
Thaddaios	-	Biblical Greek
Sabeen	-	Urdu