One bites firm end of fig (3)
I believe the answer is:
cog
'one bites firm end of fig' is the definition.
I can't judge whether this definition defines the answer.
'firm end of fig' is the wordplay.
'firm' becomes 'co' (abbreviation for company).
'end of' indicates one should take the final letters.
The final letter of 'fig' is 'g'.
'co'+'g'='COG'
Can you help me to learn more?
(Other definitions for cog that I've seen before include "minor employee" , "Tooth on the rim of gear wheel" , "Machine wheel" , "Minor player" , "bar" .)