subs. (old; now recognised).An officious bungler; a SPOIL-SPORT (q.v.). [From a character in The Busybody; see quot. 1709.]
1709. CENTLIVRE, The Busy Body, iii. 5. That unlucky dog MARPLOT is ever doing mischief, and yet (to give him his due) he never designs it. This is some blundering adventure, wherein he thought to show his friendship, as he calls it.
1764. A. MURPHY, No Ones Enemy but his Own, i. You are the very sieve of your own intentions; the MARPLOT of your own designs.
1785. GROSE, A Classical Dictionary of the Vulgar Tongue, s.v.
1844. THACKERAY, Barry Lyndon, ch. ii. p. 32. You great blundering MARPLOTyou silly beggarly brat hold your tongue!
1848. EMERSON, Spiritual Laws, Essays, 1 S. p. 125. If we will not be MARPLOTS with our miserable interferences, the work would go on far better than now.