Foster (7)
(Other definitions for nurture that I've seen before include "Rear (a child); cherish" , "Nourishment" , "Cherish (a hope)" , "Encourage to develop" , "Supply sustenance to" .)
'foster' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for nourish that I've seen before include "Feed, nurture" , "Provide with sustenance for growth" , "Feed - encourage to develop" , "Nurture, sustain" , "Foster or cherish, often with food" .)