I think service is an overloaded term. It's so generic that you can probably attach dozens of meanings to it, but here's two: One interpretation is a piece of code that doesn't neatly fit in one domain object (domain service). The other is a piece of code grabbing stuff from the db, orchestrating some domain methods, maybe wrapping it in a transaction, and exposing all that as an endpoint (application service). I think one of you has one in mind and the other the other.