bilateral

American  

[bahy-lat-er-uhl] / baɪˈlæt ər əl /

adjective

1. pertaining to, involving, or affecting two or both sides, factions, parties, or the like.

   a bilateral agreement; bilateral sponsorship.

2. located on opposite sides of an axis; two-sided, especially when of equal size, value, etc.

3. Biology. pertaining to the right and left sides of a structure, plane, etc.

4. Chiefly Law. (of a contract) binding the parties to reciprocal obligations.

5. through both parents equally.

   bilateral affiliation.

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noun

1. Informal. a bilateral agreement, especially regarding international trade.

bilateral British  

/ baɪˈlætərəl /

adjective

1. having or involving two sides

2. affecting or undertaken by two parties; mutual

   a bilateral treaty

3. denoting or relating to bilateral symmetry

4. having identical sides or parts on each side of an axis; symmetrical

5. sociol relating to descent through both maternal and paternal lineage Compare unilateral

6. relating to an education that combines academic and technical courses

7. a bilateral meeting

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Other Word Forms

• bilateralism
  noun
• bilaterally
  adverb
• bilateralness
  noun

Etymology

Origin of bilateral

First recorded in 1765–75; bi- ¹ + lateral

Explanation

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.

Example Sentences

Spokesman Dmitry Peskov said Putin and Xi would focus on bilateral ties as well as international matters.

From BBC • May 15, 2026

America’s bilateral goods deficit with China has already fallen to $221 billion in 2025 from $442 billion in 2018 — a 50% reduction over seven years.

From MarketWatch • May 14, 2026

U.S. officials and analysts expect Trump and Xi to repeat their usual displays of bonhomie but make few political breakthroughs in bilateral ties.

From The Wall Street Journal • May 13, 2026

The US president is expected to attend an arrival ceremony with Xi at the Great Hall of the People, before the two leaders hold bilateral talks.

From BBC • May 13, 2026

To those who are genuinely concerned, I push a button to say, “I have spastic bilateral quadriplegia, also known as cerebral palsy. It limits my body, but not my mind.”

From "Out of My Mind" by Sharon M. Draper

Related Words

• mutual
• reciprocal