A one syllable laugh like "heh" or "hah" that in most cases is used when following a simple statement or comment that is somewhat humorous. Can also be used as a courtesy laugh.
Dude One: "Jebus man, my shoe is tied all funny."
Dude Two: "hah"
Dude One: "Thanks for the gigglet."
Dude Two: "Of course... heh."
To be struck with an incessant laughing/giggle fit that keeps going on and on at inconvenient times, rendering you fucked because now you lookweird.
Person 1: *sitting in a classroom which is currently silent then happens to think of a funny line from Pineapple Express that strikes a chord* AhahahahahahahahaHAHAHAbuah! *clutching stomach, tears streaming down face, trying to be quiet but failing*
(gi gl bitch) noun (plural: gi gl bitch es) a person, usually female, and frequently in pairs, that laughs hysterically at something stupid and/or inside jokes, oblivious to any surrounding situations, people, or sleepers. Frequently makes fun of others' laughter when not gigglebitching, and does not realize that she sounds more annoying.
can also be verbed, as in "gigglebitching"
Cassie and Hallie were being gigglebitches this afternoon when they were giggling incessantly at god-only-knows-what, while poor Allie was out of the loop, and increasingly annoyed.