pilot bread vs sea biscuit

pilot bread and sea biscuit both are nouns.

Word	Noun	Adjective	Verb	Adverb
pilot bread	Yes	No	No	No
sea biscuit	Yes	No	No	No

As nouns, pilot bread and sea biscuit are synonyms defined as:

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

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

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