köken: Literally, “until our reunion; that we may see again”. Probably a calque of French au revoir. Compare further Italian arrivederci, German Low German up Wiederseihen (Paderbornisch), Dutch tot ziens, English until we meet again and see you, and similar forms in many languages of the world.
köken: Borrowed from Medieval Latin ad Deum (“to God”). Compare Aragonese, Asturian, Extremaduran, and Spanish adiós, Catalan adeu, Dutch ajuus, English, French, and Occitan adieu, German tschüss, Greek αντίο (antío), Galician adeus, Italian addio, Maltese addiju, Mirandese adius, Romanian adio, Serbo-Croatian ади̏о/adȉo, Slovene adȋjo.
köken: Borrowed from Classical Persian اَلوِدَاع (alwidā'), an unadapted borrowing from Arabic الوَدَاع (al-wadāʕ), whence also विदा (vidā, “departure”). Cognate with Turkish elveda.
hi (greeting) · hey (to get someone's attention) · bye (often repeated twice: hei hei)
köken: From Proto-Finnic *hei (compare Estonian hei, Ingrian hei, Karelian hei, Ludian hei, Veps hei). Compare also Old Norse hei (whence Swedish hej) and English hey.
köken: Non-Sino-Vietnamese reading of Chinese 朝 (“to meet; to meet a senior person; to attend the emperor's audience”, SV: triều). Doublet of chầu and triều. (Nguyễn Văn Khang. Từ ngoại lai trong tiếng Việt, 2007) False cognate of Italian ciao, which also means both "hello" and "goodbye".