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

And so these interviews, that these asylum officers conduct, gives the applicant a place to explain those and talk through them in, again, that non-adversarial environment. — Dana Taylor, USA Today, 3 Aug. 2026

Yaroch used his top-secret security clearance to log on to government databases and memorize the passphrases associated with adversarial accounts. — Max Grinstein, The Washington Examiner, 3 Aug. 2026

The pilot sets up interesting tensions between Duke and surrogate father Kingsley and a livelier adversarial role for Pinnock, but Kingsley is gone for the majority of the six episodes (out of eight) sent to critics and Pinnock’s absence is felt. — Daniel Fienberg, HollywoodReporter, 30 July 2026

The goal was to find and fix the vulnerabilities before hackers and adversarial governments like China began using similar tools to find and exploit them for espionage and sabotage. — Renee Dudley, ProPublica, 29 July 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