In proverbial similes, as dry as (a) bone, hard as (a) bone, white as (a) bone, etc. Cf. compounds 4.

Completely or extremely dry; entirely free from liquid or moisture. Cf. dry as a bone at bone, n.1 phrases 2.

Very dry; thirsty. Also figurative: desirous.

Of food: extremely dry; flaky or crumbly as a result of dryness. Also figurative: dull, uninteresting. Now rare.

as dry as straw, very dry.