Fruitful (8)
'fruitful' is the definition.
(associated in meaning)
This is all the clue.
(Other definitions for fertile that I've seen before include "Fruitful" , "Rich in growth" , "Let rife (anag)" , "Highly productive" , "Fecund" .)
'fruitful' is the definition.
(similar in meaning)
This is all the clue.
(Other definitions for prolific that I've seen before include "Very fertile, productive" , "having many children" , "Intellectually productive" , "Producing much" , "Rich" .)