Hardtack and Rusk

Hardtack noun - Very hard unsalted biscuit or bread; a former ship's staple.

Rusk and hardtack are semantically related in hard topic. In some cases you can use "Rusk" instead a noun "Hardtack".

Rusk noun - Slice of sweet raised bread baked again until it is brown and hard and crisp.

Hardtack and rusk are semantically related in hard topic. You can use "Hardtack" instead a noun "Rusk".