HILARIOUS JOKE is a term used to describe a joke that is particularly funny and elicits a strong reaction from the audience. GASSER, with 6 letters, is a slang term for a joke that is so funny it makes you laugh out loud. RIOT, with 4 letters, is another slang term for a joke that is extremely funny and causes an uproar of laughter. KNEESLAPPER, with 11 letters, is a term used to describe a joke that is amusing but not necessarily uproarious.