English Reference

Word

bilateral

Phoneticsbi·lat·er·al, stress on the second syllable

US/baɪˈɫætɝəɫ/

UK/baɪlˈætəɹəl/

Definitions

01between two groups

C1 · Advanced Formal

adj. involving two groups or countries, especially in an official agreement.

adj. involving two parties, groups, or nations, typically in a formal or diplomatic context.

“The two countries signed a bilateral trade agreement to lower taxes on imports.”

“The bilateral negotiations stalled when neither delegation was willing to compromise on the sensitive issue of maritime borders.”

Usage

Commonly used in political and legal contexts to describe treaties or talks.

Synonyms

mutualtwo-sidedjoint

02having two sides

C1 · Advanced Science Technical

adj. having two sides or parts that are the same.

adj. relating to or having two sides; specifically having symmetry where the left and right sides are mirror images.

“Most animals, including humans, have bilateral symmetry.”

“The biologist noted that the specimen exhibited perfect bilateral symmetry, with identical markings on both the left and right wings.”

Synonyms

Antonyms

03family descent

C2 · Proficiency Academic · Technical

adj. tracing your family history through both your mother's and father's side.

adj. relating to a system of kinship where descent is traced through both the maternal and paternal lines.

“In many modern societies, people follow a bilateral system of family history.”

“The researcher argued that bilateral descent patterns provided a more flexible social structure than strictly patrilineal systems.”

Antonyms

unilineal

04a meeting

C1 · Advanced Countable noun Formal

n. a formal meeting between two people or groups.

n. a formal discussion or meeting held between two parties, especially in diplomacy.

“The president held a bilateral with the prime minister before the main summit.”

“Following the general assembly, the two leaders retired to a private room for a bilateral to discuss regional security.”

Collocations

Common phrases and expressions where native English speakers use the word “bilateral” in context.

01. bilateral relations

Real-World Examples

“However, Russia’s 2022 invasion of Ukraine prompted Japan to impose sanctions on personnel and entities linked to Moscow, souring bilateral relations.”
The Guardian 13 Aug 2026
“Justice minister Liisa Pakosta told the BBC that Estonia would not rent jail cells to other countries while it was housing criminals from Sweden in its half-empty Tartu prison under a bilateral deal.”
The Guardian 13 Aug 2026
“Bangladesh has lashed out at India for allowing the ousted prime minister Sheikh Hasina to address journalists in New Delhi, plunging already strained bilateral relations to a fresh low.”
The Guardian 6 Aug 2026

Etymology

From bi- + lateral.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Domain

Anthropology

This entry

Exam level
CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.C1 AdvancedIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.7.0–8.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 5.0–5.595–113TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.945–990
Frequency
Frequent
Level
C1 · Advanced
Updated

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English Reference