While the word classification is intuitively clear, the word regression does not seem to imply a predictor of a continuous label. According to the Webster dictionary, regression is:
"a return to a former or less developed state."
It does also mention a special definition for statistics as a measure of the relation between the mean value of one variable (for example, output) and corresponding values of other variables (for example, time and cost), which is actually correct these days. However, historically, the regression coefficient was meant to signify the hereditability of certain characteristics, such as weight and size, from one generation to another, with the hint of planned gene selection, including humans (http://www.amstat.org/publications/jse/v9n3/stanton.html). More specifically, in 1875, Galton, a cousin of Charles Darwin and an accomplished 19th-century scientist in his own right, which was also widely criticized for the promotion of eugenics, had distributed...