overridable

• overrideable

c. 1938 override +‎ -able

overridable (not comparable)

1. That can be overridden.

   Antonyms: nonoverridable, unoverridable

• overridable is much more common than overrideable and nonoverridable; unoverridable is so rare as not to be found in Google Ngram Viewer.

• overridable, overrideable, nonoverridable, unoverridable at the Google Books Ngram Viewer.