hardtack vs pilot bread

hardtack and pilot bread both are nouns.

Word	Noun	Adjective	Verb	Adverb
hardtack	Yes	No	No	No
pilot bread	Yes	No	No	No

As nouns, hardtack and pilot bread are synonyms defined as:

hardtack and pilot bread: very hard unsalted biscuit or bread; a former ship's staple

Other synonyms of hardtack include pilot biscuit, sea biscuit, ship biscuit.

hardtack (noun)	pilot bread (noun)
very hard unsalted biscuit or bread; a former ship's staple	very hard unsalted biscuit or bread; a former ship's staple
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