noun

1. A meeting, especially one that is unplanned or unexpected.

   “Their encounter was a matter of chance.”

2. A hostile, often violent meeting; a confrontation, skirmish, or clash, as between combatants.

3. A match between two opposing sides.

Synonyms: brush, clash, confrontation, skirmish

verb

1. To meet (someone) or find (something), especially unexpectedly.

2. To confront (someone or something) face to face.

3. To engage in conflict, as with an enemy.

   “Three armies encountered at Waterloo.”