1. (v. t.) To injure by working secretly; to destroy or overthrow by clandestine measure; to undermine.

2. (v. t.) To expend too little work upon; as, to underwork a painting.

3. (v. t.) To do like work at a less price than; as, one mason may underwork another.

4. (v. i.) To work or operate in secret or clandestinely.

5. (v. i.) To do less work than is proper or suitable.

6. (v. i.) To do work for a less price than current rates.

7. (n.) Inferior or subordinate work; petty business.