Slang; from lesbians in the military who have competitions to see who can last longest, the word comes from the sound made by several ladies masturbating at the same time.
by Auric the Rad November 17, 2003
"Thrapping" Adj. : Rapping (a form of ethnic poetry with an instrumental backing or Acapella) done by one who resembles a thumb.
by Thrapper561 September 30, 2017