compunctious

• compunctuous

From the stem of compunction +‎ -ous; compare factious. Apparently taken up in modern use from Macbeth by William Shakespeare (see quotation).^[1][2]

compunctious (comparative more compunctious, superlative most compunctious)

1. Exhibiting compunctions, scruples, feelings of guilt.
   • c. 1606 (date written), William Shakespeare, “The Tragedie of Macbeth”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act I, scene v], page 134, columns 1–2:

     Come you Spirits,
     That tend on mortall thoughts, vnſex me here,
     And fill me from the Crowne to the Toe, top-full
     Of direſt Crueltie: make thick my blood,
     Stop vp th’acceſſe, and paſſage to Remorſe,
     That no compunctious viſitings of Nature
     Shake my fell purpoſe, nor keepe peace betweene
     Th’effect, and hit.

   • 1796, Edmund Burke, A Letter to a Noble Lord:

     Nothing can be conceived more hard than the heart of a thoroughbred metaphysician. It comes nearer to the cold malignity of a wicked spirit than to the frailty and passion of a man. It is like that of the principle of evil himself, incorporeal, pure, unmixed, dephlegmated, defecated evil. It is no easy operation to eradicate humanity from the human breast. What Shakspeare calls “the compunctious visitings of nature” will sometimes knock at their hearts, and protest against their murderous speculations. But they have a means of compounding with their nature. Their humanity is not dissolved. They only give it a long prorogation.