B1
the container that you sit or lie in to wash your body
Dictionary examples:
My cat thinks the bathtub is a giant water bowl for her. (0.0)
My dad uses the bathtub to wash his car keys. They're very clean! (0.0)
I tried to fit an elephant in my bathtub. It didn't work! (0.0)
Did you clean the bathtub? (15.2)