Breast (5)
I believe the answer is:
bosom
'breast' is the definition.
(I know that bosom is a type of breast)
This is the entire clue.
(Other definitions for bosom that I've seen before include "5 [BUST]" , "This friend is dear and close" , "Breast, chest" , "Woman's breast" , "Chest; very close (friend)" .)