A warm, casual way to say hello. It is the sort of greeting you toss to a friend, a classmate, or someone you are happy to see — not to a school principal, and not in a job interview. It sounds like hi and you squashed together, and that is close to the truth: it was shortened from how are you?, with a push from the already-common hi. It caught on in the United States in the 1940s and then travelled; you will hear it in British English too, especially among people who like a bouncy hello. You may also see hi-ya. There is another hi-ya that fight scenes shout when someone kicks. That one is just a made-up fighting sound, not a greeting. This word is the hello. Though actually, even as a hello it is already a little faded for some younger texters, who might just send hi or a sticker instead — but in speech, hiya still walks into a room with a smile.