West Indian chest modelled for those in a coven (7)
Solution – witches
This clue involves both an abbreviation and an anagram. (See sidebar below popular posts for links to explanations of various clue types)
The abbreviation in the solution is WI for West Indies/an
“modelled” is the word that indicates an anagram is involved – in this case of “chest”
So, wi + tches = witches who are found in covens.