undoable

• IPA^(key): /ʌnˈduː.ə.bəl/

From un- + doable.

undoable (comparative more undoable, superlative most undoable)

2. Not doable; impossible to do.

• unundoable

undoable (plural undoables)

1. Something that cannot be done; an impossible or impractical task.

From undo + -able.

undoable (comparative more undoable, superlative most undoable)

2. Possible to undo; reversible.
   • 2003, Suzanne Sayegh Thomas, Using QuarkXPress 6.0, page 87:

     Many new functions and commands are undoable and a maximum of 30 commands are undoable and redoable.