jack•legPronunciation: ( jak'leg"), [key] Chiefly South Midland and Southern U.S.
unskilled or untrained for one's work; amateur: a jackleg electrician.
unscrupulous or without the accepted standards of one's profession: a jackleg lawyer.
an unskilled or unscrupulous itinerant worker or practitioner.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.