big of one

big of (one)

Noble or commendable. This phrase is often said sarcastically. Wow, you're actually going to spend time with your brother tonight? That's big of you. It's big of you to reconcile with people who have wronged you in the past.
See also: big, of
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

big of one

Generous of one, as in It was big of Bill to give his brother his entire paycheck. This expression may be used either straightforwardly (as above) or sarcastically, as in How big of you to save the absolute worst seat for me. [c. 1940]
See also: big, of, one
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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