nothing if not

nothing if not (something)

Most characteristically (something); (something) more than any other thing. In this phrase, "not" is always followed by a modifier of some kind that is emphasized as the most prominent attribute. He's nothing if not generous—that's his third donation this week. I am nothing if not patient, but even I have my breaking point.
See also: if, not, nothing
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

nothing if not

Above all else, as in He was nothing if not discreet. Shakespeare used this idiom in Othello (2:1): "I am nothing if not critical." [c. 1600]
See also: if, not, nothing
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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