Tchau

Tchau: An informal portuguese word used in Brazil derived from the Italian word “Ciao”, a salute that means either “Hello” or “Goodbye”. However, in Brazil it is not used as an initial greeting – instead, it is a common substitute for the word “Adeus” – “Goodbye” in Portuguese.

Common usage:
– Tchau, Diana. Vemo-nos amanhã.
– Tchau, Diana. We’ll see each other tomorrow.

– Tudo bem, João. Tchau.
– Allright, João. Tchau.

Source: urbandictionary.com