One may be within call, as in the garden (5)
I believe the answer is:
lilac
'the garden' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.
'one may be within call' is the wordplay.
I cannot really understand how this works, but
'one' could be 'i' (Roman numeral) and 'i' is found within the answer.
an anagram of 'call' is 'llac' which is within the left over letters.
No letters remain.
This explanation may well be incorrect...
'as in' acts as a link.
Can you help me to learn more?
(Other definitions for lilac that I've seen before include "Tree with pink blossoms" , "Drop by about one, turning" , "Light-purple" , "Shade" , "Pale mauve colour for a flower" .)