HomeCornucopia • Word Formation 3know • (ac)quaint • agnostic • can • cognition • diagnose • gnome • ignore • recognise • reconnaissance


  • acknowledge, acknowledg(e)ment, best-known, better-known, don’t-know, foreknowledge, know-(it-)all, knowbot, know-how, (un)knowing(ly), knowledge(able), knowledgeably, knowledge-based, (un)known, know-nothing(s), lesser-known, need-to-know, self-knowledge, unacknowledged, unbeknown(st), unknowable, well-known
  • acquaint(ance), acquaintanceship, acquainted, quaint(ly), quaintness, reacquaint, unacquainted
  • (pre)cognition, (pre)cognitive, cognizance, cognizant, cognoscenti, incognito, (face-/facial-)recognition, (un)recognisable, recognizably, (de)recognise, recogniz(s)ance, unrecognised
  • agnosia, agnostic(ism), (mis)diagnose, (mis)diagnosis, diagnostic, prognosis, prognostic(ation)
  • ignoramus, ignorance, ignorant(ly), ignore, pig-ignorant
  • can(not), ken, uncouth; gnome, gnomic; connoisseur, reconnaissance, reconnoitre



  • Old English cnāwan (earlier gecnāwan) ‘recognise, identify’, of Germanic origin; from an Indo-European root shared by Latin (g)noscere, Greek gignōskein, also by can and ken.
  • The ancient root of know is shared by can and ken, ‘to know’ in Scots (all Old English), and also by Latin noscere, and Greek gignōskein ‘to know’, source of words such as agnostic. To know in the biblical sense, meaning ‘to have sex with’, comes from biblical uses such as the verse in the book of Genesis: ‘And Adam knew Eve his wife; and she conceived, and bare Cain.’ To know the ropes is to be thoroughly acquainted with the way in which something is done. The phrase comes from the days of sailing ships, when skill in handling ropes was essential for any sailor—an alternative is know their onions. The ancients valued self-knowledge as the way to wisdom—inscribed on the Greek temple of Apollo at Delphi were the words know thyself. The line ‘It’s life, Jim, but not as we know it’ is the mainstay of anyone trying to do an impression of Dr Spock from the TV series Star Trek, but he never said it in the programme. He did say that there was ‘no life as we know it’, but the quoted phrase is from the 1987 song ‘Star Trekkin’’ by the Firm.


  • Middle English: from Old French acointier ‘make known’, from late Latin accognitare, from Latin accognoscere, from ad- ‘to’ + cognoscere ‘come to know’.
  • In the Middle Ages quaint meant ‘wise, clever’, and ‘ingenious, cunningly designed, or skilfully made’. Another early sense was ‘beautiful or elegant’. Over time these meanings led to the more general notion of ‘out of the ordinary’. The current use, describing something interestingly unusual or old-fashioned, is found from the late 18th century—before this, the word had become quite rare. It comes from Old French cointe, from Latin cognoscere ‘to know’, which is the root of words such as acquaint (Middle English), literally ‘to make known to’; cognoscenti (late 18th century) from Italian for ‘those who know’; incognito; and recognise.


  • Mid 19th century: from a- ‘not’+ gnostic.
  • This word was actually invented by a specific person and then successfully entered the language. It was coined by the Victorian biologist Thomas Huxley (1825–95) to describe his own beliefs: he did not believe in God but did not think one could say for sure that God did not exist. Before Huxley devised agnostic there was no word for such a religious position. He is said to have first used it in 1869 at a party held in Clapham, London, prior to the formation of the Metaphysical Society. Huxley formed the word from the Greek a- ‘not’ and gnostos ‘known’.


  • Old English cunnan ‘know’ (in Middle English ‘know how to’), related to Dutch kunnen and German können; from an Indo-European root shared by Latin gnoscere ‘know’ and Greek gignōskein ‘know’.
  • Nowadays a can is a cylindrical metal container, but its ancestor, Old English cann, was a general word for any container for liquids. It may come from Latin canna (from cannon). If someone carries the can they take responsibility for a mistake or misdeed. The origin of this expression is uncertain, but it probably started life as early 20th-century naval slang. One theory is that it refers to the beer can or keg which one sailor carried for all his companions. An early version was to carry the can back, which might have referred to returning the empties. In film-making and recording you can talk about something being in the can when it has been captured on tape or film to a satisfactory standard. Though videotape and digital recordings are not stored in cans, the older expression has been transferred to them.


  • This is a modern Latin formation from Greek, from diagignōskin ‘distinguish, discern’, from dia ‘apart’ and gignōskein ‘recognize, know’.


  • Late 16th century: from Greek gnōmē ‘thought, opinion’ (related to gignōskein ‘know’), or Mid 17th century: from French, from modern Latin gnomus, a word used by Paracelsus as a synonym of Pygmaeus, denoting a mythical race of very small people said to inhabit parts of Ethiopia and India (compare with pygmy).
  • You would not really confuse a gnome with a pygmy, but the terms are closely related. It was probably the Swiss physician Paracelsus (c.1493–1541) who coined gnome as a synonym of Pygmaeus, the name given to a member of a mythical race of very small people believed to live in parts of Ethiopia and India. The gnomes of Zurich are Swiss financiers or bankers, thought of as having a sinister influence over international monetary funds. Former British Prime Minister Harold Wilson popularised the phrase in 1956: ‘All these financiers, all the little gnomes in Zurich and other financial centres about whom we keep on hearing’. Gnomic (early 19th century) meaning ‘clever but hard to understand’, as in ‘gnomic utterances’, is a different word. It comes from Greek gnōmē ‘thought, judgement’, which was related to gignōskein ‘to know’.


  • Late 15th century (in the sense ‘be ignorant of’): from French ignorer or Latin ignorare ‘not know, ignore’, from in- ‘not’ + gno-, a base meaning ‘know’. Current senses date from the early 19th century.


  • Mid 17th century: from Italian, literally ‘unknown’, from Latin incognitus, from in- ‘not’ + cognitus (past participle of cognoscere ‘know’).
  • The word incognito, ‘having your true identity concealed’, came from Italian in the mid 17th century. The Latin root is cognoscere ‘to know’. At first incognito could mean simply ‘unknown’, without any implication of disguise or concealment, and was used mainly of royals or dignitaries who did not want to be recognised. In the 20th century the theatre critic Kenneth Tynan (1927–80) wrote, ‘The disguise…renders him as effectively incognito as a walrus in a ballet-skirt’.


  • Late Middle English (earliest attested as a term in Scots law): from Old French reconniss-, stem of reconnaistre, from Latin recognoscere ‘know again, recall to mind’, from re- ‘again’ + cognoscere ‘learn’.
  • To recognise someone is literally to know them again, from Latin recognoscere, from re- ‘again’ and cognoscere ‘to know’. Already in Latin this had developed logical extensions to the senses such as ‘examine, acknowledge, certify’. It was in these legal senses that the word first entered English, alongside recognition. Its use to mean ‘know by some distinctive feature’ dates only from the early 18th century. Reconnaissance (early 19th century) and reconnoitre (early 18th century) both come from the French form of the word, reconnoître.


  • Old English uncūth ‘unknown’, from un- ‘not’ + cūth (past participle of cunnan ‘know, be able’).
  • A word that originally meant ‘unknown’. For much of the history of uncouth, most people would not have used or understood its opposite, couth. This originally meant ‘known’ but was later only used in Scottish English, for ‘kind’ or ‘comfortable’. Uncouth, though, developed a fully independent life. It came to refer to unsophisticated language or style in the late 17th century, and then to uncultured or ill-mannered people or behaviour. In 1896 the English essayist and critic Max Beerbohm (1872–1956) was the first to use couth as a deliberate opposite of uncouth meaning ‘cultured, well-mannered’. Ungainly (early 17th century) developed in a similar way. There is a word gainly, but it has never been common and its original meaning, ‘suitable, fitting’, now occurs only in Scottish dialect. Gainly came from the old word gain, which was used especially in the senses ‘kindly’ and ‘convenient’, and is of Scandinavian origin.

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