What is the meaning of confrontation?

noun

• A bold challenge.
• Discord resulting from a clash of ideas or opinions.
• A hostile disagreement face-to-face.
  • synonyms: encounter, showdown, face-off
• The act of hostile groups opposing each other.
  • usage: "the government was not ready for a confrontation with the unions"; "the invaders encountered stiff opposition"
  • synonyms: opposition
• A focussed comparison; bringing together for a careful comparison. .