also low-brow, "person who is not intellectual," 1902, from low (adj.) + brow (n.). Said to have been coined by U.S. journalist Will Irwin (1873-1948), perhaps on the model of highbrow, which seems to be earlier. A low brow on a man as a sign of primitive qualities was common in 19c. fiction, but on a woman it was considered a mark of classical beauty.
A low brow and not a very high one is considered beautiful in woman, whereas a high brow and not a low one is the stamp of manhood. ["Medical Review," June 2, 1894]As an adjective from 1913.