Golf club's president's first to speak (6)
I believe the answer is:
putter
'golf club's' is the definition.
(type of golf club)
'president's first to speak' is the wordplay.
'president's first' becomes 'p' (1st letter of 'president').
'to speak' becomes 'utter' ('utter' can be a synonym of 'speak').
'p'+'utter'='PUTTER'
(Other definitions for putter that I've seen before include "Club to use on the green" , "Club used on the green" , "Golf club used on greens" , "Type of golf club" , "Golf-club" .)