Definition of rag:
a piece of cloth torn off; a tattered piece of cloth; a shred; a tatter; a fragment; hence, mean or tattered attire; worn-out dress
"the song mapleleaf rag has a pleasant, bouncy tune."
at; to rate; to tease
; to torment; to banter; (slang) To drive a car or another vehicle in a hard, fast or unsympathetic manner