palooka
A stupid or a clumsy oaf, and by extension, an incompetent prizefighter. Joe Palooka, the heavyweight boxing hero of Ham Fisher's cartoon strip that ran from 1921 to 1984, was anything but inept, but even his skills and the strip's popularity couldn't save the word from its negative meaning. Calling someone a “big palooka,” unless said in a jovial and friendly context, isn't likely to win you any fans and may win you a bloody nose. The word may have been a corruption of “Pollack,” the pejorative term for Polish people.