FUBSY
third letter must be N as FUNKY to FUNNY didn't drop a hit, and FU??? is already proven. therefore, it can't be the F,U, or the K. It can't be the Y either because FURRY only has two which must come from the FU. therefore, F,U,K, and Y are ruled out so the remaining letter, that is, N, must be the third letter.
EDIT: oops, didn't see that GIZMO. I want to replace FUBSY with FUZZY. sorry.