Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun hardtack

2 senses of hardtack

Sense 1
hardtack, pilot biscuit, pilot bread, sea biscuit, ship biscuit -- (very hard unsalted biscuit or bread; a former ship's staple)
       => biscuit -- (small round bread leavened with baking-powder or soda)

Sense 2
hardtack -- (a mountain mahogany)
       => mahogany, mahogany tree -- (any of various tropical timber trees of the family Meliaceae especially the genus Swietinia valued for their hard yellowish- to reddish-brown wood that is readily worked and takes a high polish)