apposite
/əˈpɒsɪt, ˈæpəsɪt/Definitions
1. adjective
exactly opposite in meaning or effect; opposing
“The opposing views on the matter were apposite and reflected the deep divisions in the community.”
2. noun
a word or phrase that is exactly opposite in meaning or effect
“The word ‘fast’ has an apposite, ‘slow’, which is used to describe the opposite condition.”