I now wish I knew how to do that teeny-tiny print thing that some posters use, when they say, "Now donning flame-proof suit" as they rapidly exit!
Sinister comes from the Latin:sinistra which means left side or left handed. Dexterous: from Latin means right side or right handedness. Ambidextrous means being capable of using either had with "dexterity" or right handedness. Thank You Mrs Gromley, (my Latin teacher).
As a matter of fact, the ratio of right handedness to left handedness is about 85% to 15%. I read an article where, during the Middle Ages, many people who were left handed were persecuted as witches because left handedness was far from the norm. This is where the term sinister took on it's current meaning of an evil, bad, nogoodnik or action.
Class is out for today.