What is the common term for a lavatory?

A lavatory is commonly referred to as a bathroom or washroom sink. This terminology is widely accepted in plumbing and everyday language as it describes the fixture used for washing hands, face, or other personal hygiene activities in a bathroom setting. The term "lavatory" itself originates from the Latin word "lavare," which means "to wash," emphasizing its primary function.

The other options refer to different types of fixtures. A kitchen sink is designed specifically for food preparation and dishwashing, a bathtub is used for bathing and soaking, and a shower basin (often found in a shower stall) is where water collects during a shower. Each of these fixtures serves a unique purpose, distinct from that of a lavatory sink which is specifically intended for handwashing and personal care in a bathroom environment.