ilkyoudaoicibaDictYouDict[ilk 词源字典]
ilk: [OE] Historically ilk means simply ‘same’. Its Old English form was ilca, which was ultimately a compound made up of the demonstrative particle *i- ‘that (same)’ and *līk- ‘form’ (as in the English verb like). It had virtually died out by the mid-16th century as a straight synonym for same, but one context in which it survived, particularly in Scottish English, was in the increasingly fossilized phrase of that ilk ‘of the same’, which was used originally to express the notion that someone’s name was the same as that of the place they came from: thus Nairn of that ilk would have signified ‘someone called Nairn from a place called Nairn’.

In due course it came to be applied specifically to landed Scottish families, and so strong did the connection with ‘family’ become that by the 19th century we see the first signs of ilk being treated as if it were a noun, meaning ‘family’. That led on in time to an even more general sense ‘type, sort’, capable of use in such expressions as ‘of a different ilk’.

[ilk etymology, ilk origin, 英语词源]
ill: [12] ‘Sick’ is not the original meaning of ill. To start with it meant ‘bad’ (a sense which survives, of course, in contexts such as ‘ill-will’, ‘illmannered’, etc), and ‘sick’ did not come on the scene until the 15th century. The word was borrowed from Old Norse illr, which is something of a mystery: it has other modern descendants in Swedish illa and Danish ilde ‘badly’, but its other relations are highly dubious (Irish olc has been compared) and no one knows where it originally came from. The sense ‘sick’ was probably inspired by an impersonal usage in Old Norse which meant literally ‘it is bad to me’.
=> like
illicit: see leisure
illuminate: [16] Etymologically, illuminate is a parallel construction to enlighten. It was formed in the late Latin period from the prefix in- and lūmen ‘light’ (source of English luminous). The past participle of the resulting illumināre gave English illuminate. The medieval-sounding sense ‘illustrate manuscripts’ is actually quite recent, replacing in the 18th century the parallel formation enlumine, acquired by English in the 14th century via Old French enluminer from medieval Latin inlūmināre. Illumine [14] came via Old French illuminer. Illustrate is closely related.
=> illustrate, luminous
illusion: [14] The notion of ‘play’ is at the etymological heart of illusion (as indeed of its close relatives allusion [16], delusion [15], and elude [16]). It came via Old French from Latin illūsiō, a derivative of illūdere ‘make fun of’. This was a compound verb formed from the prefix in- and lūdere ‘play’ (source of English ludicrous [17]). In classical Latin illūsiō meant ‘mockery’, and no semantic shift seems to have taken place until post-classical times, when it moved to ‘deceit’ (a sense originally taken over by English).
=> allusion, delusion, elude, ludicrous
illustrate: [16] Illustrate is closely related etymologically to illuminate. It goes back to Latin illustrāre, a compound verb formed from the prefix in- and lustrāre ‘make bright’, which came from the same base as produced Latin lūmen (source of illuminate) and lūx ‘light’, and indeed English light. Originally it meant literally ‘throw light on’, but this eventually passed via ‘elucidate’ to, in the 17th century, ‘exemplify’ and ‘add pictures to’.

More of the original sense of ‘brightness’ survives, albeit metaphorically, in illustrious [16], which comes from Latin illustris ‘shining, clear’, a back-formation from illustrāre.

=> illuminate, illustrious, light, luminous, lustre
image: [13] Latin imāgō meant a ‘likeness of something’ (it probably came from the same source as imitate). It subsequently developed a range of secondary senses, such as ‘echo’ and ‘ghost’, which have not survived the journey via Old French into English, but the central ‘likeness’ remains in place. Derived from the noun in Latin was the verb imāginārī ‘form an image of in one’s mind, picture to oneself’, which became English imagine [14]. (Latin imāgō, incidentally, was used in the 1760s by the Swedish naturalist Linnaeus for an ‘adult insect’ – based on the Latin sense ‘natural shape’, the idea being that the insect had achieved its final perfect form after various pupal forms – and English took the term over at the end of the 18th century.)
=> imitate
imbecile: [16] Etymologically imbecile means ‘without support’, hence ‘weak’. It came via French from Latin imbēcillus, a compound adjective formed from the prefix in- ‘not’ and an unrecorded *bēcillum, a diminutive variant of baculum ‘stick’ (from which English gets bacillus and bacterium). Anyone or anything without a stick or staff for support is by extension weak, and so the Latin adjective came to mean ‘weak, feeble’. This broadened out to ‘weak in mind’, and was even used as a noun for ‘weak-minded person’, but English did not adopt these metaphorical uses until the late 18th century.
=> bacillus, bacterium
imitate: [16] Latin imitāri meant ‘make a copy of’. It was formed from the base *im-, which also lies behind the Latin ancestors of English emulate [16] and image; all three words share the basic meaning element ‘likeness’. English acquired the word via the Latin past participle imitātus.
=> emulate, image
immaculate: [15] A macula in Latin was a ‘spot’ or ‘stain’ (as well as a ‘hole in a net’, which gave English the mail of chain mail). Hence anything that was immaculātus (an adjective formed with the negative prefix in-) was ‘spotless’ – ‘perfect’.
=> chainmail
immediate: see medium
immense: see measure
immerse: see merge
imminent: see prominent
immolate: see mill
immune: [15] The -mune of immune is the same as that of remunerate and of commune (and hence of common). It represents Latin mūnis ‘ready to give service’. The addition of the negative prefix in- gave immūnis, which in classical Latin denoted literally ‘exempt from a service, charge, etc’, and hence by metaphorical extension ‘free from something, devoid of something’. This general sense still survives, of course, in English (as in ‘grant immunity from prosecution’); and the more specific ‘not liable to infection’ did not emerge until as recently as the 1870s, probably under the influence of French or German.
=> common, commune, remunerate
immure: see mural
imp: [OE] Old English impe meant ‘new shoot, sapling’. Its ultimate source was medieval Latin impotus ‘graft’, a borrowing from Greek émphutos, which itself was an adjective derived from the verb emphúein ‘implant’. In the early Middle English period it began to be transferred from plants to people, carrying its connotations of ‘newness’ or ‘youth’ with it, so that by the 14th century it had come to mean ‘child’.

And in the 16th century, in a development similar to that which produced the now obsolete sense of limb ‘naughty child’, it was applied to ‘mischievous children, children of the Devil’, and hence to ‘mischievous or evil spirits’.

impair: [14] If to repair something is to ‘put it right’, it seems logical that to impair something should be to ‘make it wrong’. In fact, though, logic has nothing to do with it, for the two words are quite unrelated. Repair comes ultimately from Latin parāre ‘make ready’, whereas impair goes back via Old French empeirier to Vulgar Latin *impējōrāre ‘make worse’.
impeach: [14] Impeach has nothing to do with peaches. In fact it is closely related to impede, and indeed originally meant ‘impede’ in English. Both verbs comes ultimately from Latin pēs ‘foot’. Impede [17] goes back to Latin impedīre, a compound verb based on pēs which originally meant literally ‘tie the feet together’. Impeach, on the other hand, comes via Old French empecher (ancestor of modern French empêcher) from late Latin impedicāre ‘fetter, entangle, ensnare’, a compound verb based on the noun pedica ‘fetter’, which itself came from the same base as pēs.

Its original meaning ‘impede, prevent’ survived in English until the late 17th century (‘a Ditch of sufficient breadth, and depth, to impeach the Assaults of an Enemy’, William Leybourn. Cursus Mathematicus 1690). Its use for ‘charge, accuse’ arose in the 14th century from an erroneous association with Latin impetere ‘attack, accuse’ (source of English impetuous).

=> foot, impede, pedal