decimateyoudaoicibaDictYouDict[decimate 词源字典]
decimate: [17] Decimate is a cause célèbre amongst those who apparently believe that words should never change their meanings. The original general signification of its Latin source, the verb decimāre, was the removal or destruction of one tenth (it was derived from Latin decem ‘ten’), and it may perhaps strike the 20th century as odd to have a particular word for such an apparently abstruse operation.

It does, however, arise out of two very specific procedures in the ancient world: the exaction of a tax of one tenth (for which indeed English has the ultimately related word tithe), and the practice in the Roman army of punishing a body of soldiers guilty of some crime such as mutiny by choosing one in ten of them by lot to be put to death. Modern English does not perhaps have much use for a verb with such specialized senses, but the general notion of impassive and indiscriminate slaughter implied in the Roman military use led, apparently as early as the mid- 17th century, to the modern sense ‘kill or destroy most of’.

=> decimal, ten[decimate etymology, decimate origin, 英语词源]
deckyoudaoicibaDictYouDict
deck: [15] Ultimately, deck (both the noun and the verb) is the same word as thatch. The meaning element they share is of a ‘covering over the top’. The noun was borrowed from Middle Dutch dec, which meant ‘covering’ in general, and more specifically ‘roof’ and ‘cloak’ (its ultimate source was Germanic *thakjam, source of English thatch).

Its modern nautical sense did not develop in English until the early 16th century, and as its antecedents suggest, its original signification was of a covering, perhaps of canvas or tarpaulin, for a boat. Only gradually has the perception of it changed from a roof protecting what is beneath to a floor for those walking above. The word’s application to a pack of cards, which dates from the 16th century, perhaps comes from the notion of the cards in a pile being on top of one another like the successive decks of a ship.

The verb deck [16] comes from Middle Dutch dekken ‘cover’.

=> detect, thatch, toga
declareyoudaoicibaDictYouDict
declare: [14] To declare something is to make it ‘clear’. English acquired the word from Latin dēclārāre ‘make clear’, a compound verb formed from the intensive prefix - and clārāre ‘make clear’, a derivative of clārus ‘clear’.
=> claret, clear
declineyoudaoicibaDictYouDict
decline: [14] The notion underlying decline is of ‘bending away’. It comes via Old French decliner from Latin dēclināre ‘turn aside, go down’, a compound verb formed from the prefix -, ‘away, aside’ and clināre ‘bend’, which also produced English incline and recline and is related to lean. Its Latin nominal derivative dēclinātiō has bifurcated in English, to produce declination [14] and, via Old French declinaison, declension [15].

The latter is used only in the specialized grammatical sense ‘set of inflectional endings of a noun’, already present in Latin, which derives from the concept that every inflected form of a word represents a ‘falling away’ from its uninflected base form (the same underlying notion appears in the term oblique case ‘any grammatical sense other than the nominative or vocative’, and indeed the word case itself, whose etymological meaning is ‘fall’; and there are perhaps traces of it in inflection, literally ‘bending’).

=> declension, incline, lean, recline
decorateyoudaoicibaDictYouDict
decorate: [16] Decorate comes from Latin decorātus, the past participle of decorāre ‘make beautiful’, a verb derived from decus ‘ornament’. Its root, decor-, also produced the adjective decorus ‘beautiful, seemly’, from which English gets decorous [17] and, via its neuter singular form, decorum [16]. Décor is a 19th-century borrowing from French, where it was a derivative of the verb décorer. From the same ultimate source come decent and dignity.
=> decent, dignity, decorous
decoyyoudaoicibaDictYouDict
decoy: [16] Dutch kooi means ‘cage’ (it comes from Latin cavea ‘cage’, source of English cage). The term came to be applied specifically to a pond which had been surrounded with nets into which wildfowl were lured for capture. English took it over, but brought with it the Dutch definite article de, so that Dutch de kooi ‘the decoy’ became English decoy.
=> cage
decreaseyoudaoicibaDictYouDict
decrease: [14] Etymologically, decrease means ‘ungrow’. It comes from de(s)creiss-, the present stem of Old French de(s)creistre, which was a descendant of Vulgar Latin discrēscēre. This was an alteration of Latin dēcrēscēre, a compound verb formed from the prefix -, denoting reversal of a previous condition, and crēscēre ‘grow’ (source of English crescent and a wide range of other words).
=> crescent, croissant, increase
decreeyoudaoicibaDictYouDict
decree: see discern
decrepityoudaoicibaDictYouDict
decrepit: [15] The underlying meaning of decrepit is ‘cracked’. It comes from Latin dēcrepitus, an adjective formed (with the intensive prefix -) from the past participle of crepāre ‘creak, rattle, crack’ (ultimate source also of English crepitation, crevice, and probably craven).
dedicateyoudaoicibaDictYouDict
dedicate: see indicate
deedyoudaoicibaDictYouDict
deed: [OE] Etymologically, a deed is ‘that which is done’. An ancient word, it can be traced back as far as a hypothetical *dhētis, a noun derived from *dhē-, *dhō- ‘place, put’, the Indo- European base from which do comes. This passed into Germanic as *dǣdiz, which produced German tat, Dutch daad, and Swedish dåad as well as English deed. The word’s application to a legal document is a 14th-century development.
=> do
deed pollyoudaoicibaDictYouDict
deed poll: [16] Contrary to what the term’s modern pronunciation might seem to suggest, with the main stress on its first element rather than its second, a deed poll is a sort of deed, not a sort of poll. It originally referred to a legal document made and signed by one person only. Such documents were drawn up on parchment cut evenly, or ‘polled’, rather than indented, as was the case with documents relating to two or more people.
deepyoudaoicibaDictYouDict
deep: [OE] Deep is a member of a quite extensive and heterogeneous family of English words. It comes from a prehistoric Germanic *deupaz (source also of German tief, Dutch diep, and Swedish djup), which was a derivative of the base *d(e)u- ‘deep, hollow’. This may also have been the ancestor of the first syllable of dabchick ‘little grebe’ [16] (which would thus mean literally ‘diving duck’), while a nasalized version of it may underlie dimple. It produced dip, and a variant has given us dive.
=> dabchick, dimple, dip, dive
deeryoudaoicibaDictYouDict
deer: [OE] In Old English, dēor meant ‘animal’ in general, as opposed to ‘human being’ (as its modern Germanic relatives, German tier, Dutch dier, and Swedish djur, still do). Apparently connected forms in some other Indo-European languages, such as Lithuanian dusti ‘gasp’ and Church Slavonic dychati ‘breathe’, suggest that it comes via a prehistoric Germanic *deuzom from Indo-European *dheusóm, which meant ‘creature that breathes’ (English animal and Sanskrit prānin- ‘living creature’ have similar semantic origins).

Traces of specialization in meaning to ‘deer’ occur as early as the 9th century (although the main Old English word for ‘deer’ was heorot, source of modern English hart), and during the Middle English period it became firmly established, driving out ‘animal’ by the 15th century.

defalcateyoudaoicibaDictYouDict
defalcate: [15] Defalcate comes from medieval Latin dēfalcāre ‘cut off’, a compound verb formed from the prefix - ‘off’ and falx ‘sickle’ (source of French faux ‘scythe’). At first it meant simply ‘deduct’ in English; the modern legal sense ‘embezzle’ did not develop until the 19th century.
defameyoudaoicibaDictYouDict
defame: [14] The main source of defame (originally, in Middle English, diffame) is Old French diffamer, which came from Latin diffāmāre ‘spread damaging rumours about’, a compound verb formed from the prefix dis-, denoting ‘ruination’, and fāma ‘report, fame’ (source of English fame).
=> fame
defeatyoudaoicibaDictYouDict
defeat: [14] Etymologically, to defeat someone is literally to ‘undo’ them. The verb comes from Anglo–Norman defeter, a derivative of the noun defet. This in turn came from Old French desfait, the past participle of the verb desfaire. This was a descendant of medieval Latin disfacere, literally ‘undo’, a compound verb formed from the prefix dis-, denoting reversal, and Latin facere ‘do, make’.

Its original metaphorical extension was to ‘ruination’ or ‘destruction’, and the now central sense ‘conquer’ is not recorded in English before the 16th century. A classical Latin combination of facere with the prefix - rather than dis- produced defect, deficient, and deficit.

=> defect, deficient, deficit
defectyoudaoicibaDictYouDict
defect: see deficient
defendyoudaoicibaDictYouDict
defend: [13] Defend comes via Old French defendre from Latin dēfendere ‘ward off’, a compound verb formed from the prefix - ‘off, away’ and an element that survives elsewhere only in other compound forms (represented in English by offend). It has been suggested that this is related to Sanskrit han- ‘strike’ and Old English gūth ‘battle’, and that it can be traced ultimately to a prehistoric Indo-European *gwendh-.

Defend
had not long become established in English when it produced the offspring fend, dispensing with the first syllable. This in turn formed the basis of the derivatives fender [15] and forfend [14]. Fence likewise comes from defence.

=> fence, fend
deferyoudaoicibaDictYouDict
defer: English has two distinct verbs defer. The one meaning ‘delay’ [14] is ultimately the same words as differ. It comes via Old French differer from Latin differre ‘carry apart, delay’, a compound verb formed from the prefix dis- ‘apart’ and ferre ‘carry’ (related to English bear). The Latin verb’s past participle, dīlātus, is the source of English dilatory [15]. Defer ‘submit’ [15] comes via Old French deferer from Latin dēferre ‘carry away’, a compound verb formed from the prefix - ‘away’ and ferre.

The notion of submission seems to have arisen from an earlier application to referring, or ‘carrying’, a matter to someone else.

=> bear, dilatory