From ignore + -able.

ignorable

1. Able to be ignored.

   Users on this Internet chat system are ignorable by right-clicking the user name.

2. Insignificant or trivial enough to be ignored.

   Synonyms: negligible, neglectable, trivial, insignificant

   Antonyms: unignorable, noticeable, important, radical, significant

3. (statistics, of missing data) Unrelated to the parameters being estimated

   Antonyms: informative

• French: ignorable
• German: vernachlässigbar
• Italian: ignorabile
• Portuguese: ignorável
• Spanish: ignorable

ignorable (plural ignorables)

1. Anything that can be ignored.
   • 1969, Michael Huxley, The Geographical Magazine, volume 42, page 389:

     So long as people like Mr Spearing stop at this point and resort to adjectives instead of numbers, so long will engineers, and probably also decision makers, continue to treat intangibles as ignorables.