n. 1 resistance, antagonism. 2 the state of being hostile or in conflict or disagreement. 3 contrast or antithesis. 4 a a group or party of opponents or competitors. b (the Opposition) Brit. the principal parliamentary party opposed to that in office. 5 the act of opposing or placing opposite. 6 a diametrically opposite position. b Astrol. & Astron. the position of two heavenly bodies when their longitude differs by 180ø, as seen from the earth. oppositional adj.
[ ME f. OF f. L oppositio (as OB-, POSITION) ]