Make a whoopsie (4)
I believe the answer is:
goof
(Other definitions for goof that I've seen before include "Foolish mistake" , "foolish error" , "In slang, bungle or blunder" , "Blunder, mistake (slang)" , "(Make a) silly mistake" .)
I believe the answer is:
goof
(Other definitions for goof that I've seen before include "Foolish mistake" , "foolish error" , "In slang, bungle or blunder" , "Blunder, mistake (slang)" , "(Make a) silly mistake" .)