英语词源字典 - 在线词源网站

during [during 词源字典]: during: [14] During, like durable [14], durance [15], duration [14], duress, and endure [14], comes ultimately from the Latin adjective dūrus ‘hard’. This goes back to an earlier *drūros, which is related to Irish dron ‘solid’, Lithuanian drūtas ‘strong, solid’, and Sanskrit dāruna- ‘strong, hard’, and links with Irish daur ‘oak’ (a possible relative of druid) and Greek drus ‘oak’ suggest that its original underlying meaning was ‘oak wood’, from which ‘hard’ developed as a metaphorical extension.

The Latin verb dūrāre meant originally literally ‘harden’, but this widened (perhaps with memories of an underlying sense ‘strong, resilient’) to ‘continue in existence, last’. It is these notions of ‘continuance’, ‘strength’, and ‘perseverance’ that emerge in different proportions in durable, duration, and endure, and indeed in during, which is a translation of Old French durant, the present participle of durer ‘last’: phrases such as ‘during the day’ mean etymologically ‘as long as the day lasts’. Durance, an archaic term for ‘imprisonment’, originally denoted ‘length of sentence’, and so is virtually equivalent to the modern ‘for the duration’.
=> durable, duration, duress, endure[during etymology, during origin, 英语词源]
eternal: eternal: [14] Something that is eternal lasts literally for ‘aeons’. The word comes via Old French eternal from aeternālis, a late Latin development of the Latin adjective aeternus ‘eternal’. This in turn was a derivative of aevum ‘age’ (which crops up in English medieval, primeval, etc), a relative of Greek aión ‘age’ (from which English gets aeon) and archaic English aye ‘ever’.
=> aeon, aye, ever
iconoclast: iconoclast: [17] The original iconoclasts were members of the Eastern Orthodox church in the 8th and 9th centuries AD who were opposed to the use or worship of religious images. In more extreme cases their opposition took the form of smashing icons (the word iconoclast comes via medieval Latin from medieval Greek eikonoklástēs, a compound formed from eikón ‘icon’ and the verb klan ‘break’).

The term subsequently came to be applied to extreme Protestants in England in the 16th and 17th centuries who expressed their disapproval of graven images (and popish practices in general) in similar ways. Its general use for an ‘attacker of orthodoxy’ dates from the early 19th century.
ground zero (n.): 1946, originally with reference to atomic blasts. In reference to the Sept. 11, 2001, terrorist attack on New York, it was in use by Sept. 13.
seven-year itch (n.): 1899, American English, some sort of skin condition (sometimes identified with poison ivy infection) that either lasts seven years or returns every seven years. Jocular use for "urge to stray from marital fidelity" is attested from 1952, as the title of the Broadway play (made into a film, 1955) by George Axelrod (1922-2003), in which the lead male character reads an article describing the high number of men have extra-marital affairs after seven years of marriage.
tenet (n.): "principle, opinion, or dogma maintained as true by a person, sect, school, etc.," properly "a thing held (to be true)," early 15c., from Latin tenet "he holds," third person singular present indicative of tenere "to hold, grasp, keep, have possession, maintain," also "reach, gain, acquire, obtain; hold back, repress, restrain;" figuratively "hold in mind, take in, understand."

The Latin word is from PIE root *ten- "to stretch" (cognates: Sanskrit tantram "loom," tanoti "stretches, lasts;" Persian tar "string;" Lithuanian tankus "compact," i.e. "tightened;" Greek teinein "to stretch," tasis "a stretching, tension," tenos "sinew," tetanos "stiff, rigid," tonos "string," hence "sound, pitch;" Latin tendere "to stretch," tenuis "thin, rare, fine;" Old Church Slavonic tento "cord;" Old English þynne "thin"). Connecting notion between "stretch" and "hold" is "cause to maintain." The modern sense is probably because tenet was used in Medieval Latin to introduce a statement of doctrine.
mesophyll: "The inner tissue (parenchyma) of a leaf, containing many chloroplasts", Mid 19th century: from meso- 'middle' + Greek phullon 'leaf'.