A drink, to the fit, may be a mere bagatelle! (8)
'a mere bagatelle' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'a drink to the fit' is the wordplay.
'a drink' becomes 'pint' (pint is a unit of liquid volume).
'to the fit' becomes 'able' (I've seen this in another clue).
'pint'+'able'='PIN-TABLE'
'may be' acts as a link.
Can you help me to learn more?
(Other definitions for pin table that I've seen before include "Game with balls on a sloping surface" , "play bagatelle here" .)