verb
goofs; goofed; goofing
chiefly US informal :to make a careless or stupid mistake :to make a goof [no obj]
usually + up
goof around
[phrasal verb] chiefly US informal :to spend time doing silly or playful things
goof off
[phrasal verb] chiefly US informal :to spend time doing things that are not useful or serious
goof on
[phrasal verb]
goof on (someone or something) US slang :to make jokes about (someone or something) in a way that is either playful or unkind
noun
plural goofs
[count] chiefly US informal
a silly or stupid person
a careless or stupid mistake