interjection
Very casual slang greeting, a contraction of こんにちは. Used among close friends or in informal settings, similar to 'hey' or 'yo'.
See also: こんにちは
ちーっす、元気?
Hey, how's it going?
朝、友達に「ちーっす」と声をかけた。
In the morning, I greeted my friend with 'yo'.