Yes, sailors pine (5)
I believe the answer is:
yearn
'pine' is the definition.
('yearn' can be a synonym of 'pine')
'yes sailors' is the wordplay.
'yes' becomes 'yea' (I've seen this before).
'sailors' becomes 'rn' (abbreviation for Royal Navy).
'yea'+'rn'='YEARN'
(Other definitions for yearn that I've seen before include "Ache, crave" , "lust" , "Feel desire" , "Have a great longing" , "Hanker" .)