Definition of "hardtack"

hardtack

noun
countable and uncountable, plural hardtacks
1. (nautical) A large, hard biscuit made from unleavened flour and water; formerly used as a long-term staple food aboard ships.
  Quotations
  Philander went into the next room […] and came back with a salt mackerel that dripped brine like a rainstorm. Then he put the coffee pot on the stove and rummaged out a loaf of dry bread and some hardtack.
  1913, Joseph C[rosby] Lincoln, chapter VIII, in Mr. Pratt’s Patients, New York, N.Y., London: D[aniel] Appleton and Company
  Bread and fodder had to be brought up over longer and longer distances, it was more difficult all the time, transport was lacking, the army had already eaten two-thirds of its hardtack, exhausted men were marching in baking heat along sandy roads into emptiness!
  1989, Aleksandr Solzhenitsyn, translated by H. T. Willetts, August 1914, Farrar, Straus and Giroux, page 71