Perverse extremists, refusing to acknowledge term is discriminatory (6)
I believe the answer is:
sexist
'discriminatory' is the definition.
(similar in meaning)
'perverse extremists refusing to acknowledge term is' is the wordplay.
I cannot really understand how this works, but
'is' is found in the answer.
The remaining letters 'sext' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for sexist that I've seen before include "discriminating against women?" , "Bigot" , "Offensive about a particular gender" , "Chauvinistic" , "discriminating sort" .)