1. Used as an expression of strong feeling or emotion: Susan's mother spoke to her, "Hello! Don't you realize what you are doing!"
2. A means of expressing surprise: Greg commented, "Hello! You're finished already!"
3. Etymology: alteration of hallo, which is an alteration of hollo, holla, which is a shout to attract attention. Perhaps from holla!, "stop, cease!"

A greeting: Mildred was getting friendly hellos from her colleagues for the great work that she did on the project.

1. To say or to shout as a greeting: James helloed Mike when they met downtown.
2. Used to welcome someone in a friendly way, on the phone, in e-mails, etc.: The clerk at the store answered the phone by saying, "Hello, this is Jeremy, how may I help you?"

In fact, Jeremy was helloing people many times every day.

Joe started his e-mail with, "Hello Marlon, it was good to hear from you again."