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

• 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

The Norwegian Sea test marks the Air Force’s latest effort to integrate anti-ship weaponry onto its aircraft to counter rising adversarial naval challenges. —Kapil Kajal, Interesting Engineering, 11 Sep. 2025

Pivot to Asia All of this shapes India’s policy toward China to manage an adversarial relationship with limited cooperation and convergences. —Shyam Saran, Time, 10 Sep. 2025

This includes some restrictions on shipping technology to adversarial countries and avoidance of anything deemed woke by the current administration. —Jim McGregor, Forbes.com, 8 Sep. 2025

Newsom has taken an adversarial role in Trump’s debate over National Guard deployment, issuing a statement on Tuesday celebrating Breyer’s court ruling. —Molly Parks, The Washington Examiner, 3 Sep. 2025

Word History

Etymology

adversary entry 1 + -al entry 1

First Known Use

1839, in the meaning defined above

Rhymes for adversarial

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

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