A person you would say "hi" and "bye" to casually, but little more. Generally someone desirable as an acquaintance and not anything more.
From "This American Life"
From "This American Life"
by flykiddoc August 18, 2009
Get the hi bye friendmug. I have 34 hi and bye friends
by George Humphery November 3, 2017
Get the hi and bye friendsmug.