Ancient temple tower (8)
I believe the answer is:
ziggurat
'ancient temple tower' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for ziggurat that I've seen before include "Type of pyramid" , "Babylonian temple" , "Ancient tiered temple" , "Stepped pyramid of ancient Mesopotamia - zig at rug (anag)" , "Temple tower" .)