Gentle as nurse (6)
I believe the answer is:
tender
I believe this clue is a double definition.
'gentle' is the first definition.
(similar in meaning)
'nurse' is the second definition.
(a nurse tends to patients)
'as' is the link.
(Other definitions for tender that I've seen before include "Gentle, fond (6)" , "Make bid as for contract" , "easily damaged" , "Ship that provides supplies to other ships" , "... is the Night/F Scott Fitzgerald" .)