When something is bilateral it has two sides or it affects both sides of something. Discussions between two political parties are called bilateral because both sides get to share their views.

Bilateral comes from Latin: bi means "two" and lateralis means "belonging to the side." Debates about issues can be described as bilateral — as long as people on both sides get to speak. However, bilateral can describe anything with two sides, like some of the organs in the body: the brain, heart and lungs all have two distinct sides.

Definitions of bilateral
  1. adjective
    having two sides or parts
    synonyms: two-sided
    many-sided, multilateral
    having many parts or sides
  2. adjective
    having identical parts on each side of an axis
    synonyms: bilaterally symmetric, bilaterally symmetrical, isobilateral
    symmetric, symmetrical
    having similarity in size, shape, and relative position of corresponding parts
  3. adjective
    affecting or undertaken by two parties
    “a bilateral agreement between the United States and Japan”
    mutual, reciprocal
    concerning each of two or more persons or things; especially given or done in return
Word Family

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