Unripe (5)
'unripe' is the definition.
(synonyms)
This is all the clue.
(Other definitions for immature that I've seen before include "Green" , "Lacking in development" , "Not yet adult or fully developed" , "Undeveloped - unripe" , "Not yet fully-developed" .)
'unripe' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for green that I've seen before include "Immature" , "Inexperienced - olive coloured" , "right environmentally" , "Not yet ripe" , "Gullible" .)