The name biscuit is said to be derived from the Latin panis biscoctus
meaning twice cooked bread.
The product that this referred to was ship’s biscuits. These were made
by cooking a dough and then drying out the product.
The drying out was the only available way of lowering the moisture
content sufficiently to preserve the product. As the product consisted of
just flour and water, cooked and dried, the end result must have been
unpleasant.