Sneakers put pressure on boat crew crossing line (8)
I believe the answer is:
prowlers
'sneakers' is the definition.
Although both the answer and definition are plural nouns, I don't see how they can define each other.
'pressure on boat crew crossing line' is the wordplay.
'pressure' becomes 'p' (scientific abbreviation).
'on boat crew' becomes 'rowers' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'crossing' means one lot of letters goes inside another (to cross can mean to go over or around).
'line' becomes 'l' (used when specifying particular lines from a poem).
'rowers' going around 'l' is 'rowlers'.
'p'+'rowlers'='PROWLERS'
'put' is the link.
Can you help me to learn more?