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.

• (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.
• certifiable at OneLook Dictionary Search

• rectifiable