Old man circling church to avoid dog (9)
I believe the answer is:
dachshund
'dog' is the definition.
(I know this)
'old man circling church to avoid' is the wordplay.
'old man' becomes 'dad' (synonyms).
'circling' means one lot of letters goes inside another (circling can mean going around or containing).
'church' becomes 'ch' (common abbreviation).
'to' means one lot of letters go next to another.
'avoid' becomes 'shun' (shunning is a kind of avoiding).
'ch'+'shun'='chshun'
'dad' enclosing 'chshun' is 'DACHSHUND'.
(Other definitions for dachshund that I've seen before include "Sausage 11" , "Long, low dog" , "Long-bodied, short-legged breed of dog" , "Small dog (from Germany?)" , "Sausage dog" .)