1560s, from hard (adj.) + wood (n.). That from deciduous trees, as distinguished from that from pines and firs. Bartlett ("Dictionary of Americanisms," 1848) defines it as "A term applied to woods of solid texture that soon decay, including generally, beech, birch, maple, ash, &c. Used by shipwrights and farmers in Maine, in opposition to oak and pine."
hardship
hardtack
hard-up
hardware
hard-wired
hardwood
hard-working
hardy
hare
Hare Krishna
hare-brained