Sinistral and dextral, in some scientific fields, are the two types of chirality ('handedness') or relative direction. Sinistral and dextral, in some scientific fields, are the two types of chirality ('handedness') or relative direction. The terms are derived from the Latin words for 'left' (sinister) and 'right' (dexter). Other disciplines have different terms (such as dextro- and laevo-rotary, in chemistry, or clockwise and anticlockwise in physics) or simply use left and right (as in anatomy).