English

Noun

unthank ‎(uncountable)

1. Lack or absence of thanks or thankfulness; thanklessness; unthankfulness; ill-will.
   • 2000, Francis G. Snyder, The Europeanisation of Law:

     It is always by this unthank that things are given to the observer that we pretend to have access to the truth of the word.

2. Harm; injury; misfortune.

   Unthank come on his head that bound him so. — Chaucer.

Etymology 2

From un- +‎ thank.

Verb

unthank ‎(third-person singular simple present unthanks, present participle unthanking, simple past and past participle unthanked)

1. (transitive) To recant; unsay, as what has been said by way of acknowledgement.
2. (transitive) To undo or withcall one's thankfulness; negate, cancel, or revoke one's thanks.