Pineapple and some bananas -- green bananas -- chopped by a date (4,7)
I believe the answer is:
hand grenade
'pineapple' is the definition.
(pineapple can informally mean a grenade)
'and some bananas green bananas chopped by a date' is the wordplay.
I cannot really understand how this works, but
an anagram of 'and' is 'nad' which is present in the answer.
'some' could be 'a' and 'a' is present in the answer.
'date' could be 'd' (abbreviation e.g. dob - date of birth) and 'd' is present in the answer.
an anagram of 'green' is 'ngree' which is located in the remaining letters.
A single letter 'h' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for hand grenade that I've seen before include "Tree with edible nuts" , "Small explosive device for throwing" , "Small explosive device used in close combat" , "Small thrown bomb" , "Manually launched explosive device" .)