Webster's Revised Unabridged Dictionary · 1913

Hoar

Hoar , adjective

[Old English hor, har, Anglo-Saxon hār; akin to Icelandic hārr, and to Old High German hēr illustrious, magnificent; compare Icelandic Heie brightness of the sky, Gothic hais torch, Sanskrit kētus light, torch. Compare Hoary.]

1.
White, or grayish white; as, hoar frost; hoar cliffs.
Hoar waters. — Spenser
2.
Gray or white with age; hoary.
Whose beard with age is hoar. — Coleridge
Old trees with trunks all hoar. — Byron
3.
Musty; moldy; stale. [Obsolete] — Shakespeare

Hoar , noun

Hoariness; antiquity. [Rare]
Covered with the awful hoar of innumerable ages. — Burke

Hoar , transitive verb

[Anglo-Saxon hārian to grow gray.]

To become moldy or musty. [Obsolete] — Shakespeare