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

With adversarial hypersonic weapons becoming increasingly complex and erratic, liquid rocket engines provide active throttle control and throttle range, giving them the maneuverability and flexibility needed for hypersonic defense. —Prabhat Ranjan Mishra, Interesting Engineering, 21 Sep. 2025

The Path Forward Chopra’s vision suggests that our relationship with AI need not be adversarial. —Bernard Marr, Forbes.com, 19 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

For an industry built on information asymmetry and adversarial relationships, that change can’t come soon enough. —Maya Ackerman, Fortune, 10 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