Green’s Dictionary of Slang

a pompous fool.

1847		De Quincey Spanish Nun 21: All was upset by two witnesses, whom the reader... will at once know to be false witnesses, but whom the old Spanish buz-wigs doated on as models of all that could be looked for in the best [F&H].
1854		F. Smedley Harry Coverdale’s Courtship 28: Like that fabulous humbug Pegasus, that old Buzwig is always bothering us about.