Slang (Def Leppard song) definition

(1) A characteristic language of a particular group (as among thieves)

"They don't speak our lingo"

(2) Informal language consisting of words and expressions that are not considered appropriate for formal occasions; often vituperative or vulgar

"Their speech was full of slang expressions"

(3) Abuse with coarse language

(4) Fool or hoax

"The immigrant was duped because he trusted everyone"

"You can't fool me!"

(5) Use slang or vulgar language