confrontation

(noun) a bold challenge.

(noun) discord resulting from a clash of ideas or opinions.

(noun) a hostile disagreement face-to-face. Synonyms: encounter, showdown, face-off.

(noun) the act of hostile groups opposing each other. Synonyms: opposition. Examples: "The government was not ready for a confrontation with the unions." "The invaders encountered stiff opposition."

(noun) a focussed comparison; bringing together for a careful comparison.