Definitions
1.verbTo require too little work from; to work insufficiently.
2.verbTo work or operate in secret or clandestinely.
3.verbTo do less work than necessary (on)."to underwork a painting"
4.verbTo do work for inadequate payment.
5.verbTo injure by working secretly; to destroy or overthrow by clandestine measure; to undermine.
6.verbTo do similar work for a lesser price than; to undercut."One mason may underwork another."