Part of speech: Noun
an acknowledgment that can be used to say hello or goodbye (aloha is Hawaiian and ciao is Italian)
The word "ciao" comes from Medieval Latin sclavus, which comes from Venetian ciao, which was borrowed from Italian ciao. Many other languages have similar words:
Slav – A related word in the same word family.
slave – A related word in the same word family.
Latin became the scholarly language of Europe for over 1,500 years, standardizing technical vocabulary.