Crossword Genius

Foul up (3)

Ross

I believe the answer is:

'foul up' is the definition.
(both can mean to blunder)

This is all the clue.

(Other definitions for err that I've seen before include "Miss the mark" , "Be mistaken" , "Go wrong" , "Leave the straight and narrow" , "have an affair?" .)

I've seen this clue in the Newsday, The Wall Street Journal and The New York Times.
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