Meaning of folk etymology

folk' etymol'ogy

Pronunciation: [key]
  1. a modification of a linguistic form according either to a falsely assumed etymology, as Welsh rarebit from Welsh rabbit, or to a historically irrelevant analogy, as bridegroom from bridegome.
  2. a popular but false notion of the origin of a word.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.