Curl right round fireplace (7)
I believe the answer is:
'curl' is the definition.
'right round fireplace' is the wordplay.
'right' becomes 'rt' (abbreviation as in Rt Hon- the Right Honourable).
'round' is an insertion indicator.
'fireplace' becomes 'ingle' (I've seen this before).
'rt' placed around 'ingle' is 'RINGLET'.
(Other definitions for ringlet that I've seen before include "Curl or tendril" , "Curl of hair; butterfly" , "Cluster of hair" , "A curl - kind of tingler" , "Bit of hair" .)