Chums (4)
'chums' is the definition.
('pal' can be a synonym of 'chum')
This is the entire clue.
(Another definition for pals that I've seen is " Friends".)
'chums' is the definition.
(both can mean friends)
This is all the clue.
(Other definitions for mates that I've seen before include "Friends among the ship's officers" , "Naval officers'" , "Chums" , "Pals or married couples" , "Pals, pairs" .)