Fake tigers at zoo fences (6)
I believe the answer is:
ersatz
'fake' is the definition.
(I've seen this before)
'tigers at zoo fences' is the wordplay.
'ERSATZ' is hidden in amongst the letters.
However, I am uncertain how this is indicated.
(Other definitions for ersatz that I've seen before include "Artificial, imitation - from German" , "inferior type" , "Artificial or inferior imitation" , "Made in imitation - in Germany" , "False" .)