One may snarl at a snail meandering about (8)
I believe the answer is:
alsatian
'one may snarl' is the definition.
(a dog might snarl)
'at a snail meandering about' is the wordplay.
'meandering' is an anagram indicator.
'about' is an insertion indicator.
'a'+'snail'='asnail'
'asnail' is an anagram of 'alsian'.
'at' inserted inside 'alsian' is 'ALSATIAN'.
(Other definitions for alsatian that I've seen before include "Breed of dog" , "Dog (from French border region?)" , "Large dog and someone from Alsace" , "Large dog and someone from northern France" , "Strong dog known as German Shepherd" .)