cornercap

From corner +‎ cap.

cornercap (plural cornercaps)

1. (obsolete) A priest's or academic's hat.
2. (obsolete) The chief ornament.
   • c. 1595–1596 (date written), William Shakespeare, “Loues Labour’s Lost”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act IV, scene iii]:

     Thou makest the triumviry the cornercap of society.

• “cornercap”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.