ship biscuit vs pilot biscuit

ship biscuit and pilot biscuit both are nouns.

Word	Noun	Adjective	Verb	Adverb
ship biscuit	Yes	No	No	No
pilot biscuit	Yes	No	No	No

As nouns, ship biscuit and pilot biscuit are synonyms defined as:

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

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

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