The definition of a gazabo is slang for a guy or a fellow.
The slang term you use to refer to a guy you know but don't really like is an example of gazabo.
nounpl. -·bos or -·boes
Slang a fellow; guy: often derogatory
Origin of gazabofrom Spanish gazapo, an artful knave, back-formation from gazapatón, foolish talk, ultimately from Classical Greek kakemphaton, neuter of kakemphatos, ill-sounding, equivocal
Possibly from Spanish gazapo (“sly fellow”).