Noise on boat was intrusive (6,2)
I believe the answer is:
barged in
'intrusive' is the definition.
The answer and definition are not the same part of speech. However, past participle verbs and adjectives sometimes define each other.
'noise on boat' is the wordplay.
'noise' becomes 'din' (din can mean a loud noise or disturbance).
'on' is a charade indicator (letters next to each other).
'boat' becomes 'barge' (barge is a kind of boat).
'din' after 'barge' is 'BARGED IN'.
'was' is the link.
Can you help me to learn more?
(Other definitions for barged in that I've seen before include "Intruded" , "Interrupted" .)