adversarial

adjective

ad·​ver·​sar·​i·​al ˌad-vər-ˈser-ē-əl 

ˌad-və-, 

-ˈse-rē-

: involving two people or two sides who oppose each other : of, relating to, or characteristic of an adversary or adversary procedures (see adversary entry 2 sense 2)

an adversarial relationship

an adversarial system of justice with prosecution and defense opposing each other

Synonyms of adversarial

• hostile
• negative

Examples of adversarial in a Sentence

an adversarial system of justice with prosecution and defense opposing each other

the relationship between the president and the congress should not be adversarial if anything is to get done

Recent Examples on the Web

That way, your intentions are clear, which makes the discussion less adversarial from the outset. — Melody Wilding, Contributor, CNBC, 11 Nov. 2026

Google Search is also using the technology as a safety layer to detect adversarial behavior involving Model Context Protocol (MCP) tools. — Neetika Walter, Interesting Engineering, 11 Nov. 2026

Corporate boards must be able to speak truth to power, as good governance is neither blind loyalty nor an always-adversarial mentality—and have the courage to support or reprimand a CEO under scrutiny. — Jeffrey Sonnenfeld, Time, 11 Nov. 2026

The two adversarial nations are not named in public court records. — Salvador Rizzo, Washington Post, 6 Nov. 2026

Word History

Etymology

adversary entry 1 + -al entry 1

First Known Use

1839, in the meaning defined above

Rhymes for adversarial

• biserial
• filarial
• malarial
• subaerial
• actuarial
• secretarial
• urticarial
• aerial
• areal
• ariel
• burial
• antimalarial

Kids Definition

adversarial

adjective

ad·​ver·​sar·​i·​al ˌad-vər-ˈser-ē-əl 

: involving two people or two sides who oppose each other

Legal Definition

adversarial

adjective

ad·​ver·​sar·​i·​al ˌad-vər-ˈser-ē-əl 

: of, relating to, or characteristic of an adversary or adversary procedures : adversary