Webster's Revised Unabridged Dictionary · 1913

Rath

Rath (rath) , noun

[Ir. rath.]

1.
A hill or mound. [Ireland] — Spenser
2.
A kind of ancient fortification found in Ireland.

Rath (rath) , adjective

[Anglo-Saxon hrae, hrad, quick, akin to Old High German hrad, Icelandic hraer.]

Coming before others, or before the usual time; early. [Obsolete or Poetic]
Bring the rathe primrose that forsaken dies. — Milton

Also: Rathe

Rath , adverb

Early; soon; betimes. [Obsolete or Poetic]
Why rise ye up so rathe? — Chaucer
Too rathe cut off by practice criminal. — Spenser

Also: Rathe