Meaning of mescal button

mescal' but"ton

Pronunciation: [key]
  1. one of the dried, buttonlike tops of a mescal of the genus Lophophora, used as a hallucinogen, esp. by certain Indians of Mexico and the southwestern U.S. during religious ceremonies; peyote.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.