1: Someone succeeding, despite all probable odds. Showing an impressive display of skill. Synonymous with "balling." (References the 1985 Marvel Comics character, Longshot, who briefly joined The Uncanny X-men)
Samuel was longshotting last night when he beat an entire team of prestige players all by himself in Call of Duty: Modern Warfare.
Junot Diaz was longshotting in 2008 when he won the Pulitzer Prize in Fiction.