Buddhist's heading for one to pray (3)
I believe the answer is:
beg
'to pray' is the definition.
('beg' can be a synonym of 'pray')
'buddhist's heading for one' is the wordplay.
'heading' indicates taking the first letters (head could mean the top letter).
'for one' becomes 'eg' (both can mean 'for example').
The first letter of 'buddhists' is 'b'.
'b'+'eg'='BEG'
(Other definitions for beg that I've seen before include "Implore, solicit" , "Ask for money, scrounge" , "Plead as for help" , "Plead, implore" , "Implore or cadge" .)