1 rare Of or belonging to the left hand or left-hand side; (hence) sinister; underhand; inferior or backward. Compare "left hand".
Originally with allusion to Matthew 25:33, referring to the placement of the wicked, symbolized as goats, at the left hand of Christ.
2Located on the left side; turned or orientated towards the left side.
Affecting or occurring in the left side of the body or of an organ, or the left-hand member of a bilateral pair of organs.
4Favouring, or having greater skill or acuity on the left side of the body; especially having greater strength or superior motor skills in the limbs of the left side.
Early 17th century; earliest use found in Edward Topsell (d. 1625), Church of England clergyman and author. From left + sided.