different between unban vs unbay

English

un- +? ban

unban (third-person singular simple present unbans, present participle unbanning, simple past and past participle unbanned)

(transitive) To lift a ban against.
- 2004, Paul Mutton, IRC Hacks
  ChanServ can unban you from your channel when someone has banned you […]

un- +? bay

unbay (third-person singular simple present unbays, present participle unbaying, simple past and past participle unbayed)

(obsolete, transitive) To free from the restraint of anything that surrounds or encloses.
- 1687, John Norris, A Collection of Miscellanies, consisting of Poems, Essays, Discourses and Letters
  I ought […] to unbay the current of my passion.

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