bilateral

adjective

bi·​lat·​er·​al (ˌ)bī-ˈla-t(ə-)rəl How to pronounce bilateral (audio)
1
: affecting reciprocally two nations or parties
a bilateral treaty
a bilateral trade agreement
2
: having two sides
dealing with a bilateral problem
3
biology
a
: of, relating to, or affecting the right and left sides of the body or the right and left members of paired organs
bilateral nephrectomy
b
bilaterally adverb

Did you know?

Since the prefix bi- means "two" in Latin, bilateral means essentially "two-sided". In the days when there were two superpowers, the U.S. and the Soviet Union regularly engaged in bilateral arms negotiations; such negotiations are much less common today. Sometimes bilateral refers to two sides of the same thing. A bilateral hip replacement, for instance, replaces both hip bones in the same operation. And bilateral symmetry (a term often used by biologists) refers to the fact that, in many organisms (such as humans), the left side is basically the mirror image of the right side.

Examples of bilateral in a Sentence

Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
According to InStyle, the star received the honor in recognition of her advocacy for women’s health after she was diagnosed with bilateral breast cancer in April 2023. Gabrielle Rockson, People.com, 25 Oct. 2024 What's followed has been sporadic with selection geared around routine bilateral white-ball series. Tim Ellis, Forbes, 25 Oct. 2024 She was diagnosed with bilateral breast cancer in April 2024, and has since undergone a double mastectomy and reconstruction along with other treatments. Jacqui Palumbo, CNN, 24 Oct. 2024 The pair has not held any formal bilateral meetings since. Ashok Sharma, Los Angeles Times, 23 Oct. 2024 See all Example Sentences for bilateral 

Word History

First Known Use

1751, in the meaning defined at sense 1

Time Traveler
The first known use of bilateral was in 1751

Dictionary Entries Near bilateral

Cite this Entry

“Bilateral.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bilateral. Accessed 5 Nov. 2024.

Kids Definition

bilateral

adjective
bi·​lat·​er·​al (ˈ)bī-ˈlat-ə-rəl How to pronounce bilateral (audio)
-ˈla-trəl
1
: having or involving two sides or parties
a bilateral treaty
2
: characterized by bilateral symmetry
bilaterally
adverb

Medical Definition

bilateral

adjective
bi·​lat·​er·​al (ˈ)bī-ˈlat-ə-rəl, -ˈla-trəl How to pronounce bilateral (audio)
1
: of, relating to, or affecting the right and left sides of the body or the right and left members of paired organs
bilateral nephrectomy
bilateral tumors of the adrenal glands
2
: having bilateral symmetry
bilateralism noun
bilaterality noun
plural bilateralities

Legal Definition

bilateral

adjective
bi·​lat·​er·​al ˌbī-ˈla-tə-rəl How to pronounce bilateral (audio)
: affecting, obligating, or shared by both parties
bilaterally
-rə-lē
adverb
Last Updated: - Updated example sentences
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