Instrument made from bamboo (6)
I believe the answer is:
abacus
'instrument made from bamboo' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for abacus that I've seen before include "Old counting-frame" , "frame of sorts" , "Mechanical calculator" , "You could count on this once" , "that one can count on" .)