Английский Этимологический словарь - hard (adj.)

- O.E. heard "solid, firm, not soft," also "severe, rigorous, cruel," from P.Gmc. *kharthus, from PIE *kratus "power, strength." The adv. sense was also present in O.E. Hard of hearing preserves obsolete M.E. sense of "having difficulty in doing something." Hard liquor is 1879, Amer.Eng.; hardwood is from deciduous trees, distinguished from that of pines and firs. Hardware is from 1515; in the sense of "physical components of a computer" it dates from 1947. Hard-headed is first attested 1519; hard-hearted is 12c. Hard-boiled "severe, tough" is from 1886; hard-core "tough" is 1951, extension to pornography is from 1970s. Hard up (1612) is originally nautical, of steering (slang sense of "short of money" is from c.1820), as is hard and fast (1867), of a ship on shore. Hardball in the figurative sense is from 1973; hard-on "penile erection" first recorded 1893; hard times "period of poverty" is from 1705.