dummy up

dummy up

1. To suddenly stop talking or refuse to speak, typically due to a particular reason. Naturally, everyone dummied up as soon as the check came. Our usual informant dummied up when he realized there was a mole in the department.
2. To create a mock version of something. I'm going to dummy up the layout for this month's issue before our next meeting with the boss.
See also: dummy, up
Farlex Dictionary of Idioms.

dummy up

Sl. to refuse to talk. Jill dummied up when they got her into the station. John dummied up right away when the police arrived.
See also: dummy, up
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

dummy up

v.
1. To refuse to talk or to stop talking suddenly: I was told to dummy up until my lawyer arrived.
2. To make a model of some publication or page layout: Dummy up the first page and I'll look at it. If you're finished proofreading the article, dummy it up.
See also: dummy, up
The American Heritage® Dictionary of Phrasal Verbs.

dummy up

in. to refuse to talk. (see also clam up.) Rocko dummied up right away. He’s a real thoroughbred.
See also: dummy, up
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • clam up
  • do what comes naturally
  • natch
  • leave (one) to (one's) fate
  • dismiss (someone or something) out of hand
  • nob
  • throw (oneself) at (someone's) head
  • fling (oneself) at (someone's) head
  • fling at
  • fling oneself at someone