certifiable

certify +‎ -able

certifiable (comparative more certifiable, superlative most certifiable)

1. (of a document) That can, or that must be certified.
2. (informal, of a person) Mentally ill to such an extent that involuntary institutionalization is appropriate; crazy.
   • 2015, Rosemary Sullivan, Stalin's Daughter, →ISBN, page 311:

     If any person said to you in 1950 that in seventeen years Miss Stalin would defect to the West, you would rightly have considered that person certifiable. She has now done it, with impressive smoothness and conviction.

• (mentally ill): insane, mad, nuts

• certifiably

certifiable (plural certifiables)

1. (informal) A crazy person.
   • 2009 August 22, Bob Herbert, “Voices of Anxiety”, in New York Times‎:

     Forget the certifiables who are scrawling Hitler mustaches on pictures of the president.

• “certifiable”, in The Century Dictionary […], New York, N.Y.: The Century Co., 1911, →OCLC.
• “certifiable”, in OneLook Dictionary Search.

• rectifiable