maguffy, n. — Green’s Dictionary of Slang

maguffy n.

[? a real name, but note the film jargon MacGuffin, a gimmick or plot pretext]

(W.I.)

1. one who thinks that they are more important than they really are.

1975

cited in Allsopp Dict. Carib. Eng. Usage (1996).

2. anything large and pretentious.

1976

cited in Allsopp Dict. Carib. Eng. Usage (1996).