One in form maybe always allowed outside (7)
I believe the answer is:
leveret
'one in form' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.
'always allowed outside' is the wordplay.
'always' becomes 'ever' (synonyms).
'allowed' becomes 'let' (to let is to allow or permit).
'outside' means one lot of letters goes inside another.
'ever' placed within 'let' is 'LEVERET'.
'maybe' acts as a link.
Can you help me to learn more?
(Other definitions for leveret that I've seen before include "hare about in spring" , "Young animal" , "Small hopper" , "First-year hare" , "Speedy young thing" .)