• WordNet 3.6
    • n hardtack very hard unsalted biscuit or bread; a former ship's staple
    • n hardtack a mountain mahogany
    • ***
Webster's Revised Unabridged Dictionary
    • Hardtack A name given by soldiers and sailors to a kind of unleavened hard biscuit or sea bread. Called also pilot biscuit pilot bread ship biscuit and ship bread
    • Hardtack Any of several mahogany trees, esp. the Cercocarpus betuloides.
    • ***
Century Dictionary and Cyclopedia
    • n hardtack Large, coarse, hard biscuit baked without salt and kiln-dried, much used by sailors and soldiers: ship-biscuit.
    • n hardtack Same as hardhead, 6.
    • ***


In literature:

Here we air, sir, stuck in the mud, burnin' with fever, livin' on hardtack.
"Campaigns of a Non-Combatant," by George Alfred Townsend
And there was the usual "weevily hardtack" in the bread-barge.
""Where Angels Fear to Tread" and Other Stories of the Sea" by Morgan Robertson
We were just packed as close as the squares of hardtack in the bread barrels, closer than sardines in a box.
"The Twenty-fifth Regiment Connecticut Volunteers in the War of the Rebellion" by George P. Bissell
Although given a few hardtack by her captors at the time of her release, she was getting hungry.
"The Woman with a Stone Heart" by Oscar William Coursey
When there was leisure to do it, hardtack was soaked well and then fried in bacon grease.
"Detailed Minutiae of Soldier life in the Army of Northern Virginia, 1861-1865" by Carlton McCarthy
Compared with sow-belly and hardtack, it was a feast.
"The Story of a Common Soldier of Army Life in the Civil War, 1861-1865" by Leander Stillwell
I had forgotten these hardtack.
"The Copper Princess" by Kirk Munroe
I suppose it has got to be bacon and hardtack again.
"The Boy Chums in the Forest" by Wilmer M. Ely
To make hardtack palatable toast it until crisp, or soak in hot coffee and butter it, or at least salt it.
"Scouting For Girls, Official Handbook of the Girl Scouts" by Girl Scouts
During this time we had no cooked food, nothing but hardtack and raw pork and coffee but once.
"War from the Inside" by Frederick L. (Frederick Lyman) Hitchcock

In news:

In the passionate world of Civil War re-enactors, authenticity is everything -- from uniforms with historically correct stitching to hardtack made from scratch.
Hardtack crackers and Confederate Johnny cake.
Hardtack crackers made with whole wheat flour alongside Confederate Johnny cakes.
Hardtack crackers were a main form of (despised) sustenance for all Civil War soldiers.
Hardtack crackers and Confederate Johnny cake .
Hardtack crackers made with whole wheat flour alongside Confederate Johnny cake s.
A thirst for good music is all you need to appreciate the Hardtackers Shanty Crew, an eight-person a cappella group from Columbus, Ohio.
In 19th-century sea-faring circles, avocados were known as "midshipman's butter" because sailors spread them onto hardtack.
So I checked in with Uncle Dave, just to make sure the hardtack cracker and Johnny cake recipes I found to commemorate the anniversary were "authentic".