IPA: /ˈhɑːrdˌtæk/
KK: /ˈhɑrdˌtæk/
A type of hard biscuit or bread made from flour and water, often used as a long-lasting food for sailors and soldiers.
Sailors often relied on hardtack as a staple food during long voyages at sea.
Hardtack is formed from "hard" (from Old English "heard", meaning firm or solid) and "tack" (from Middle English "tac", meaning a small piece or morsel). The word refers to a type of hard, dry biscuit or bread that was often used as a long-lasting food source, especially by sailors and soldiers.
Think of 'hard' as something firm and solid, and 'tack' as a small piece of food — that's why hardtack is a solid, durable biscuit.