opposite

directly facing each other

“they sat opposite at the table”

moving or facing away from each other

“looking in opposite directions”

the other one of a complementary pair

“the opposite sex”

characterized by opposite extremes; completely opposed

“diametrical (or opposite) points of view”

of leaves etc; growing in pairs on either side of a stem

“opposite leaves”

a contestant that you are matched against

a relation of direct opposition

something inverted in sequence or character or effect

a word that expresses a meaning opposed to the meaning of another word, in which case the two words are antonyms of each other

altogether different in nature or quality or significance

“the medicine's effect was opposite to that intended”

being directly across from each other; facing

“And I on the opposite shore will be, ready to ride and spread the alarm”