ehlo

A greeting used by people familiar with the Internet in its early days, when sending mail one had to greet the mail server by saying either 'helo' or 'ehlo'. Why 'ehlo' was included was unknown, but it is a command still in use today on SMTP servers around the world.

It is brief, and throws some people off guard who are unfamilar- but people still understand it, and most will just think of it as a misspelling.