jargon, lingo, patois, argot, vernacular, slang, cant - a characteristic language of a particular group (as among thieves); "they don't speak our lingo"

simpleton, simple - a person lacking intelligence or common sense

bridgehead, foothold - an area in hostile territory that has been captured and is held awaiting further troops and supplies; "an attempt to secure a bridgehead behind enemy lines"; "the only foothold left for British troops in Europe was Gibraltar"