adj secret; clandestine; hence, mean; unfair; fraudulent.
2. underhand ·adv in an underhand manner;
said of pitching or bowling.
3. underhand ·adv by secret means; in a clandestine manner; hence, by fraud; unfairly.
4. underhand ·adj done, as pitching, with the hand lower than the shoulder, or, as bowling, with the hand lower than elbow.