P. G. Wodehouse in 1904
Oh, Bertie, if ever I called you a brainless poop who ought to be given a scholarship at some good lunatic asylum, I take back the words.
P. G. Wodehouse - Jeeves and the Feudal Spirit (1954)
A nincompoop is a stupid or foolish person.
This noun appeared in the late 17th century in the forms nicompoop, ninkompoop, nickumpoop and nincompoop.
It is first recorded in the 1673 comedy Epsom-Wells by Thomas Shadwell (circa 1640-92):
– Mrs Bisket: Ay, Mr. Fribble maintains his Wife like a Lady, and she has all things about her as well as any Woman in the Parish, he keeps her the prettiest pacing Nag with the finest Side-saddle of any Womans in the Ward, and lets her take her pleasure at Epsom two months together.
– Mr Bisket: All this thou shalt do, my Dear; I’le omit nothing that shall please thee.
– Mrs Bisket: Yes, you Nicompoop, you are a pretty Fellow to please a Woman indeed!
It was also used by William Winstanley (1628?-1698) in Poor Robin’s True Character of a Scold, or, The Shrew’s Looking-Glass. Dedicated to all Domineering Dames, Wives Rampant, Cuckolds Couchant, and Henpeckt Sneaks, in City or Country (1678 – modernised spelling):
But now I speak of husband, methinks I see the creeping snail shivering in an ague-fit when he comes in her presence. She is worse than cow-itch* in his bed, and as good as a chafing-dish at board: but has either quite forgot his name, or else she likes it not; which makes her re-baptize him with more noble titles, as white-livered rascal, drunken sot, sneaking nincompoop (original text: ninkompoop) or pitiful lousy Tom Farthing**.
(* cowage, a leguminous climbing plant, Mucuna pruriens, with hairy pods that cause stinging and itching – ** Tom Farthing, a fool, simpleton)
In A Dictionary of the English Language (1755), Samuel Johnson suggested that nincompoop is “a corruption of the Latin non compos”, but this does not agree with the earliest forms. (This Latin expression is a shortening of non compos mentis, not master of one’s mind.)
The second element is perhaps the obsolete verb to poop, attested in 1575 and meaning to fool, deceive, itself of uncertain origin. It is perhaps related to the Dutch derogatory proper name Hans Poep, which was coined around 1600 to designate a German, especially a migrant worker from Westphalia. Poep may be from German Bube, malicious, mean person (it is the origin of Dutch boef, meaning scoundrel), with a probable allusion to Dutch poep, meaning shit. (In a similar manner, the German noun Pumpernickel literally means Nick the farter.)
Since two of the earliest forms of nincompoop were nicompoop and nickumpoop, the first element was perhaps derived from a proper name. It would therefore be comparable to the now obsolete French nouns nicaise and nicodème, designating a simple or naive person. The former is a use of the proper name Nicaise. The latter refers to Nicodemus, a Pharisee who was a member of the Jewish ruling council. He visited Jesus by night and asked him naive questions. In the New International Version, the gospel of John, 3:3-4, is:
Jesus replied, “Very truly I tell you, no one can see the kingdom of God unless they are born again.”
“How can someone be born when they are old?” Nicodemus asked. “Surely they cannot enter a second time into their mother’s womb to be born!”
This sense of nicodème is a reminiscence of a medieval mystery play of the mid-15th century, Mystère de la Passion by Arnoul Gréban, in which Nicodemus was presented as a narrow-minded character. Nicodème was altered into niquedouille (the suffix -ouille being pejorative), now dated, and into nigaud, feminine nigaude, still very common. And it is perhaps under the influence of nigaud(e) that the proper name Nicaise came to be used as a common noun.
(Because Nicodemus was afraid of being seen with Jesus and visited him at night, the noun Nicodemite designates a person who resembles him, a secret or timid adherent. It was specially used of a Protestant living in a Catholic country in the 16th century who concealed his or her faith to escape persecution.)
According to Ernest Weekley in An Etymological Dictionary of Modern English (1921), the first element in nincompoop may be from the surnames Nicodème or Nicholas. He relates it to the noun noddy*, attested in 1534 in the sense of a simpleton, which according to him might be a pet form of Nicodème. In support of this theory, he cites the following passage from Our Mutual Friend (1865), by Charles Dickens (1812-70):
“Did you ever hear of the name of Boffin?”
“No,” said Mr. Wegg, “I never did hear of the name of Boffin.”
“Do you like it?”
“Why, no,” retorted Mr. Wegg, “I can’t say I do.”
“Why don’t you like it?”
“I don’t know why I don’t,” retorted Mr. Wegg, approaching frenzy, “but I don’t at all.”
“Now, I’ll tell you something that’ll make you sorry for that,” said the stranger, smiling. “My name’s Boffin.”
“I can’t help it!” returned Mr. Wegg.
“But there’s another chance for you,” said Mr. Boffin, smiling still, “Do you like the name of Nicodemus? Think it over. Nick, or Noddy.”
“It is not, sir,” Mr. Wegg rejoined, “it is not a name as I could wish any one that I had a respect for to call me by.”
“Noddy Boffin,” said that gentleman. “Noddy. That’s my name. Noddy—or Nick—Boffin.”
Writing that the element poop means duffer, Ernest Weekley concludes:
Hence nincompoop appears to be formed like tomfool.
Incidentally, the term Tom-noddy has also been used.
However, the noun poop in the sense of a stupid or incompetent person only appeared in the late 19th century, and is probably a shortening of nincompoop. And the noun noddy might simply be derived from the verb to nod, or be a shortening of the noun noddypoll, attested around 1529 and composed of noddy, from the verb to nod, and the noun poll in the sense of a person’s head.
In the sense of a simpleton, two apparently nonce words have also existed: poopnoddy, used by John Deacon in Tobacco tortured (1616), and noddypoop, only recorded by John Florio in A Worlde of Wordes, Or Most copious, and exact Dictionarie in Italian and English (1598):
Fatappi, Doltes, fooles, noddies, guls, noddie poopes. Also a kinde of night bird. (Dolts, fools, noddies, gulls, noddypoops. Also a kind of night bird.)
(The Italian fatappi is the plural of fatappio, denoting a small bird, and figuratively a stupid and gullible person.)
* Perhaps from this common noun, Noddy is the name of a toy figure of a boy whose head is fixed in such a way that he nods when he speaks. He is the central character in a series of stories for young children by Enid Blyton (1897-1968).
Chiefly in British English, the noun Noddy is used in allusion either to Noddy’s naivety, lack of sophistication, etc., or to the simplicity or idealised nature of the stories’ setting, Toyland, in which all the characters and objects are toys.
The name of this character has been translated as Oui-Oui, Yes-Yes, in French.