blow it(redirected from blow one's lines)
slang To ruin, mishandle, or fail to capitalize on an opportunity. Bob was being considered for the promotion, but he blew it when he came in late to work each day this week. Things were going well with Steve, but I blew it by smothering him.
1. Spoil, botch, or bungle something, as in That was a great opportunity, but now I've blown it. [Slang; c. 1940]
2. 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]