it's to laugh

it's to laugh

It is totally ridiculous; it is laughable. Wait till you hear her ludicrous excuse—it's to laugh.
See also: laugh, to
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

it's to laugh

Also, it is to laugh. It is absurd, laughable, as in You think the trial will be over in a week-it's to laugh! This expression is usually put as an exclamation, as in the example. [Second half of 1900s]
See also: laugh, to
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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References in periodicals archive ?
"If he gets hit with the ball his reaction is not, "Ouch, that's sore", it's to laugh. That's what gets him going, I guess, weird things like that.