Meaning

noun a tie in tennis or table tennis that requires winning two successive points to win the game

noun the cardinal number that is the sum of one and one or a numeral representing this number

noun a word used in exclamations of confusion

originFrom Middle English dewes (“two”), from Anglo-Norman, from Old French deus, from Latin duo. The word was used by Ford Motor Co. in 1932 to describe a two-seater car model.

Etymology from Wiktionary, CC BY-SA 3.0