Arboreal feature that ran around the town centre (5)
I believe the answer is:
rowan
'arboreal feature' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'ran around the town centre' is the wordplay.
'around' is an insertion indicator.
'the town centre' becomes 'ow' (central letters of the word 'town').
'ran' enclosing 'ow' is 'ROWAN'.
'that' is the link.
Can you help me to learn more?
(Other definitions for rowan that I've seen before include "The mountain ash tree" , "Atkinson or Williams" , "Tree bearing bright red berries" , "Red-berried tree" , "Tree with orange-red berry-like fruits" .)