What is the meaning of Drei?

Spoken by a player during a match with one or more visually impaired players to indicate the third rank in algebraic notation.

three

three

three (3)

three

alternative form of drye

alternative form of dregh

imperative of dreie

we

dry

three (numerical value represented by the Arabic numeral 3; or describing a set with three elements)

to turn

three

Source: wiktionary.org