A numerical description of the flatness or roughness of a surface, especially an optical or machined surface.

plural of surface

Third-person singular simple present indicative form of surface

(meteorology) The portion of the atmosphere lying next to the surface of the earth and extending up to between 50 and 100 meters.

(mathematics) A one-dimensional complex manifold; a generalization of the complex plane.

plural of surfari

(geography) Water collecting on the ground or in a stream, river, lake, sea or ocean, as opposed to groundwater.

(aeronautics) A moveable surface attached to a machine such as an aircraft or submarine that can be used to control the machine's motion in roll, pitch or yaw.

Someone who engages in shoulder surfing.

(physics) A quantized electromagnetic wave trapped at a metallic surface through interaction with the free electrons of the metal.