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definitions

jelly roll

noun

a thin, rectangular layer of sponge cake, spread with fruit jelly and rolled up.
Slang: Vulgar.
  1. the vagina.
  2. sexual intercourse.

Origin of jelly roll

An Americanism dating back to 1890–95
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Word Origin and History for jellyroll
n.

also jelly-roll, "cylindrical cake containing jelly or jam," 1873, from jelly + roll (n.). As slang for "vagina, sexual intercourse" it dates from 1914 ("St. Louis Blues").

Online Etymology Dictionary, © 2010 Douglas Harper