Lingua franca

A lingua franca (originally Italian for "Frankish language" - see etymology below) is a language that is used between persons who do not have the same mother tongue.^[1]

The terms working language, bridge language and vehicular language are used in the same sense.

1. ↑ Viacheslav A. Chirikba, "The problem of the Caucasian Sprachbund" in Pieter Muysken, ed., From Linguistic Areas to Areal Linguistics, 2008, p. 31. ISBN 90-272-3100-1