Underhand a. : Secret; clandestine; hence, mean; unfair; fraudulent.

Underhand a. : Done, as pitching, with the hand lower than the shoulder, or, as bowling, with the hand lower than elbow.

Underhand adv. : By secret means; in a clandestine manner; hence, by fraud; unfairly.

Underhand adv. : In an underhand manner; -- said of pitching or bowling.

Example:
How can I start pitching Underhand for a guy?

Taxonomy
Merriam-Webster Online Dictionary, Dictionary, webster, Word Games, Webster Online Dictionary with audio pronunciations, adverb, Custom Search, glossary, english, language, ESL, Search, n-d, clandestine, unobtrusive manner, underhand motion, bowl, pitch.

Defination from the web:
underhand from the Merriam-Webster Online Dictionary with audio pronunciations, thesaurus, Word of the Day, and word games. ... Learn more about "underhand" and related topics at Britannica.com. See a map of "underhand" in the Visual Thesaurus. Pronunciation Symbols ...