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
Lanny	LAN-ee	English
Methodios	-	Ancient Greek
Michayla	-	English (Rare)
Glynis	-	Welsh
Gloria	GLAWR-ee-ə (English), glo-REE-ah (Italian), GLAW-ryah (Polish)	English, Italian, Spanish, Portuguese, German, Polish
Osip	O-seep	Russian