According to the parish council, it's a village. 

https://southpethertonparishcouncil.gov.uk/

In my opinion, if anyone is going to get the village/town distinction correct, it's going to be the parish council. No downsides to calling yourself a town so it's not like they're pretending to be less important than they are.

just realised that OP was anon so closing, unless you'd like to keep it open Yeoman

