Longman Dictionary of Contemporary English
thicko
noun
EXAMPLES FROM CORPUS
▪ Lysander, her hero, is a lovable thicko who isn't even terribly proficient in bed.
Wiktionary
thicko
n. (context chiefly British slang English) A dimwit or idiot.
Usage examples of "thicko".
That suddenly the entire quantum history of every particle in the visible universe--right out to the furthest quasar--suddenly jumped to one state, and all because some thicko in a bearskin had his brain wired up slightly differently to his ancestor?