Merriam-Webster's Collegiate® Dictionary, 11th Edition
FART
I. intransitive verb
Etymology: Middle English ferten, farten; akin to Old High German ferzan to break wind, Old Norse freta, Greek perdesthai, Sanskrit pardate he breaks wind
Date: 13th century
to expel intestinal gas from the anus,
II. noun
Date: 14th century
an expulsion of intestinal gas, a foolish or contemptible person