Sinistral (adj; noun): lado esquerdo, canhoto. Pertaining to or facing the left side; left-handed. "She wore her watch on her right wrist like most sinistrals."
Dextral (ajd; noun): lado direito, destro. "Twenty-four dextral students at Monash University were recruited. None had a sinistral in the immediate family, and their handedness was carefully..."
Keep in mind that "sinistral" and "dextral" refer to a particular side of an object, not the side of the person looking at it. The sinistral side is that side of an object when you are facing in the same direction as the object. "That unmotivated nebbish, Pierre LePoupe, could never climb the sinistral face of Mount Mukkimuck," refers to your right side as you look at the mountain from the approach.
"Mazel Toffe is the most dexterous sinistral I have ever heard play a violin."