Couldn't you put one straight on the boat? (6)
I believe the answer is:
banana
'couldn't you put one straight on the boat?' is the definition.
I can't judge whether this defines the answer.
'put one straight on the boat?' is the wordplay.
'put' is an insertion indicator.
'one' becomes 'an' (an apple is one apple).
'straight on the boat?' becomes 'bana' (I can't justify this - if you can you should give a lot more credence to this answer).
'an' inserted inside 'bana' is 'BANANA'.
Can you help me to learn more?
(Other definitions for banana that I've seen before include "Curved fruit (in a split dessert?)" , "Plantain-like fruit" , "Fruit that comes in a bunch" , "One out of hand" , "Fruity type" .)