Adjective. Acronym for "Hi, I'm gay." Pronounced by saying each letter individually. Used to refer to something exceptionally effeminate when exhibited by an otherwise seemingly straight individual. When someone wears something or does something that seems to shout "Hi! I'm GAY!"
Dude, you must be looking to smoke some pole, because that shirt is H.I.G.
A title given to someone that demonstrates homosexual tendencies and yet never openly states there orientation to be homosexual. This is not however for derogatory use. Those who are normally known as Higs are aware of it and comfortable with it.
John is acting particularly gay today, we must now address him as Higs.