Head of trade fit for the board (5)
I believe the answer is:
table
'the board' is the definition.
('table' can be a synonym of 'board')
'head of trade fit' is the wordplay.
'head of' suggests taking the first letters.
'fit' becomes 'able' ('able' can be similar in meaning to 'fit'**).
The first letter of 'trade' is 't'.
't'+'able'='TABLE'
'for' is the link.
(Other definitions for table that I've seen before include "Item of furniture; figures presented in columns" , "Flat-topped piece of furniture" , "put forward a > schedule" , "Data arranged in rows and columns" , "Set of figures in columns" .)