I meant to compose with key thats atmospheric (7)
I believe the answer is:
ambient
'atmospheric' is the definition.
Although both the answer and definition are adjectives, I don't see how one could define the other.
'i meant to compose with key' is the wordplay.
'to compose with' indicates an anagram.
'key' becomes 'b' (eg B major, musical key).
'i'+'meant'='imeant'
'imeant' mixed up with 'b' gives 'AMBIENT'.
'thats' is the link.
Can you help me to learn more?
(Other definitions for ambient that I've seen before include "Going round" , "Relating to the immediate surroundings" , "Surrounding, on all sides - light or temperature" , "Relating to the immediate environs" , "Going around" .)