All such wrenches are indisputably obstruction wrenches (as that's a generalization). More specifically, that model is intended for starters and manifolds...
^ I think this is another one of those "regional dialect" things like "peevee / cant hook / timberjack" or "pop / soda".
As long as your assistant hands you the correct tool when you're under the car on your back, you can call it anything you want.
Agreed, four cycle. So long as your helper/apprentice knows your terminology, it's all good. Though, I still like throwing the helpers for a loop and ask for the water pump pliers.
Oh, I call the OP's wrenches starter or half moon.
Always called the OP's pictured wrench a starter/ manifold wrench. But it falls under the broad category of obstruction wrench. Pictured here are some other examples. Starter/ manifold, modified, and door hinge wrenches