Japanese for 'goodbye'; however, it carries more finality. Instead of being used at the end of a day, as in "Goodbye see you tomorrow," it would be used in situations where you will either not see the person for a long time, if ever again.
Man: I'm sorry my trip is taking me overseas for an indefinate amount of time, I will call you as often as I can!

Woman: Sayonara! *tear*
by A Man Called Michael October 15, 2009
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Song created by Aries or Wunderworld on YouTube.

Also an informal way of saying goodbye to one another.
Man: Hey, have you heard Sayonara by Aries?
Woman: Yea, it's a pretty good song.
by icarus beats August 12, 2018
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a street in Citrus Heights ca where people living on that "block" think they are "Gangsta"
Don't mess with that fool, he is from Sayonara block.
by Juan Mendozafromsac June 21, 2007
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