IPA: /ˌæd.vɚˈsɛr.ɪ.nəs/
KK: /ædˈvɜrsəˌnɛs/
The state or quality of being in opposition or conflict with someone or something; it refers to the condition of being an opponent or rival.
The adversariness in their relationship made collaboration difficult.
Adversariness is formed from "adversus" (meaning turned against) and the suffix "-ness" (meaning the state or quality of). The word describes the state of being opposed or hostile.
Think of being 'turned against' ('adversus') someone or something, and the '-ness' indicates a state. This helps you remember that 'adversariness' refers to the quality of being opposed.