Webster's Revised Unabridged Dictionary · 1913

Bilateral

Bilateral ({not transcribed}) , adjective

[Prefix bi- + lateral: compare French bilatéral.]

1.
Having two sides; arranged upon two sides; affecting two sides or two parties.
2.
(Biology) Of or pertaining to the two sides of a central area or organ, or of a central axis; as, bilateral symmetry in animals, where there is a similarity of parts on the right and left sides of the body.