New poem about repellent domesticated worm (8)
I believe the answer is:
nematode
'worm' is the definition.
(nematode is a kind of worm)
'new poem about repellent domesticated' is the wordplay.
I cannot quite see how this works, but
'new' could be 'n' (abbreviation as in New Testament NT) and 'n' is located in the answer.
'poem' could be 'ode' (ode is a type of poem) and 'ode' is found in the answer.
'about' could be 'a' (abbreviation in Chambers) and 'a' is located in the answer.
The remaining letters 'emt' 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 nematode that I've seen before include "Long thin worm such as threadworm" , "Type of worm" , "sort of animal" .)