Synesthesia (also spelled synæsthesia or synaesthesia, plural synesthesiae or synaesthesiae)—from the Ancient Greek In one of the most common forms of synesthesia, grapheme → color synesthesia, individual letters of the alphabet and numbers (collectively referred to as graphemes), are "shaded" or "tinged" with a color. While synesthetes do not, in general, report the same colors for all letters and numbers, studies of large numbers of synesthetes find that there are some co… (More on Synesthesia)