The Collaborative International Dictionary of English v.0.48:

Unheal \Un*heal"\, n. [Pref. un- not + heal health.]
   Misfortune; calamity; sickness. [Obs.] --Chaucer.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Unheal \Un*heal"\, v. t.
   To uncover. See Unhele. [Obs.]
   [1913 Webster]