Ancient artefact (5)
I believe the answer is:
relic
'ancient artefact' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for relic that I've seen before include "Hangover from an earlier time" , "Object of historical interest" , "E,g. dead saint's bone" , "Surviving ancient custom" , "bit of old religious tradition" .)