Not all ripe tomatoes are `isweet^i (3)
I believe the answer is:
pet
''isweeti' is the definition.
I can't judge whether this definition defines the answer.
'not all ripe tomatoes are' is the wordplay.
'not all' indicates the answer is hidden within the clue (only some of the letters).
'PET' is hidden within 'ripe tomatoes are'.
Can you help me to learn more?
(Other definitions for pet that I've seen before include "Tamed animal; sulk" , "Cherished favourite" , "Loved domestic animal" , "Favourite; fit of the sulks" , "Particular favourite" .)