One briefly imprisoned for a trick?
I believe the answer is:
con
'for a trick?' is the definition.
(a con is a fraud or trick)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for con that I've seen before include "Direct steering; study" , "Scam, swindle" , "Informally swindle" , "one in pen?" , "Swindle after winning trust" .)