Au revoir and Hegira

Au revoir noun - An expression of good wishes at parting.

Hegira and au revoir are semantically related. In some cases you can use "Hegira" instead a noun phrase "Au revoir".

Hegira noun - The flight of Muhammad from Mecca to Medina in 622 which marked the beginning of the Muslim era; the Muslim calendar begins in that year.

Au revoir and hegira are semantically related. Sometimes you can use "Au revoir" instead a noun "Hegira".