There is no Opposite

As a native speaker, I have a Love/Hate relationship with the English language.
Often its subtle peculiarities will perplex me. More often I find them amusing.

One day, recently, I was struck by a thought (it left no visible bruise, fortunately). I realized there are words in the English language that simply have no antonym.
I am unable to recall or locate a word that directly opposes any of these.

For example, you cannot untell something. References to and "Untold Story" mean it has never been told. But, the act of telling cannot be reversed.

  • Exterminator
  • Assassin
  • Predict
  • Foretell
  • Annihilate
  • Exorcise
  • Tell
  • Exercise
  • Cancel
  • Pervue
  • Wimper
  • Sigh
  • Slurp
  • Swim
  • Wander
  • Anticipate
  • Evasive
  • Relent
  • Relinquish
  • Overlook
  • Overwhelm
  • Steep*
  • Inundate
  • Weed* (Ed:shouldn't this activity be called "Unweeding"?)
  • Wait
  • Wonder

    A word that is the opposite in meaning of another is called an Antonym. I would like to dub the words in this list as Unantonymic.

    I suspect this list will continue to grow (as it had until I decided to share it here).

*The verb form of these words