Short, lively party without Irish thug (8)
I believe the answer is:
hooligan
'thug' is the definition.
(I've seen this before)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for hooligan that I've seen before include "Thug, ruffian" , "Ruffian, yob" , "A young ruffian" , "Ruffian, noisy troublemaker" , "Undesirable" .)