European bores knock pretentious American protestors (3,5)
I believe the answer is:
tea party
'american protestors' is the definition.
I can't tell whether this defines the answer.
'european bores knock pretentious' is the wordplay.
I cannot really understand how this works, but
'european' could be 'e' (abbreviation e.g. EU) and 'e' is located in the answer.
'knock' could be 'tap' (synonyms) and 'tap' is found within the leftover letters.
'pretentious' could be 'arty' (similar in meaning) and 'arty' is found in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for tea party that I've seen before include "sort of celebration" , "Social gathering (for Bostonians?)" , "Social event (once held in Boston?)" , "The Mad Hatter held one" , "US political movement" .)