Lyrical fresh topic around mid-September (6)
I believe the answer is:
poetic
'lyrical' is the definition.
(I've seen this before)
'fresh topic around mid-september' is the wordplay.
'fresh' indicates anagramming the letters.
'around' means one lot of letters goes inside another.
'mid' says to take the centre.
'september' becomes 'sep' (synonyms).
The central letter of 'sep' is 'e'.
'topic' with letters rearranged gives 'potic'.
'potic' going around 'e' is 'POETIC'.
(Other definitions for poetic that I've seen before include "Like a 16" , "lines?" , "Flowery" , "Concerning metrical writing" , "Lyrical like verse" .)