1. adj. [Geology]

Pertaining to a strike-slip or left-lateral fault in which the block across the fault moves to the left; also called a sinistral strike-slip fault. If it moves to the right, the relative motion is described as dextral. Counterclockwise rotation or spiraling is also described as sinistral.

Antonyms: dextral

See related terms: fault,  strike-slip fault