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

Hosts Marisa Lagos and Scott Shafer referenced Williamson’s adversarial style. —Kate Wolffe, Sacbee.com, 15 Nov. 2025

Yoshua Bengio pioneered generative adversarial nets, two AI networks which compete with each other. —Tom Chivers, semafor.com, 13 Nov. 2025

Red Team testing subjects the system to adversarial evaluation, ensuring resilience and reliability. —Mark Howard, Time, 10 Nov. 2025

Though George Washington and the press started off amicably, their relationship grew more adversarial once journalists began criticizing the nation’s first president. —JSTOR Daily, 7 Nov. 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