Red-violet
On the old fashioned, now obsolete red-yellow-blue pigment color wheel (in which red, yellow, and blue were regarded as the primary colors and orange, green, and violet were regarded as the secondary colors), red-violet was a tertiary  color between red and violet on the red-yellow-blue pigment color wheel and thus was the equivalent of pigment purple.  The other tertiary colors on a red-yellow-blue (RYB) color wheel were called blue-violet, blue-green, yellow-green, yellow-orange, and red-orange.