To fail; make a botch; ruin one's chances: We are winning. If we don't blow it/ I think I blew it. I talked too much and said too little(1920+)
Idioms and Phrases with blow it
blow it
.
Spoil, botch, or bungle something, as in That was a great opportunity, but now I've blown it. [ ; c. 1940 ]
.
blow one's lines. Make a mistake in speaking one's part in a theatrical production, as in Ben blew his lines, but Dean came to the rescue. [ Mid-1900s ]