From the vocabulary word denoting the hardy, brightly coloured plant (Middle English hather; the spelling was altered in the 18th century as a result of folk etymological association with heath). The name was first used in the late 19th century and became particularly popular from the mid-1940s.
Finnish: from haapa ‘aspen’ + the local suffix -la. Originally it was a habitational name for someone living or working at a farmstead so named, but in other cases the surname was an ornamental adoption during the name conversion movement in the 19th and early 20th centuries. It occurs chiefly in western Finland.