Sect in "Witness” (5)
I believe the answer is:
amish
'sect in witness' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for amish that I've seen before include "Member of a sect" , "Of US Mennonites" , "American religious sect" , "US religious community" , "Relating to a strict US Mennonite sect" .)