Etymology From Middle English moth, moththe, motthe, moght, mohþe, mouȝte, from Old English moþþe, mohþe, mohþa (“any destructive insect larva”), from Proto-West Germanic *moþþō, *mottō, from Proto-Germanic *muþþô, *muttô (“moth, worm”), from Proto-Indo-European *mutn-, *mut- (“worm”). Cognate with Saterland Frisian Motte (“moth”), West Frisian mot (“moth”), Dutch mot (“moth”), German Low German Motte, Mott (“moth”), German Motte (“moth”), Swedish mott (“moth”) and Norwegian Nynorsk mott (“moth”).
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Any flying insect of the order Lepidoptera not in the superfamily Papilionoidea, most species of which are nocturnal and can be distinguished from butterflies by feather-like antennae.
Earless ghost swift moths become “invisible” to echolocating bats by forming mating clusters close (less than half a meter) above vegetation and effectively blending into the clutter of echoes that the bat receives from the leaves and stems around them.2013 May-June, William E. Conner, “An Acoustic Arms Race”, in American Scientist, volume 101, number 3, pages 206–7:
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Figuratively Anything that gradually and silently eats, consumes, or wastes any other thing.
Etymology From Middle English moth, moththe, motthe, moght, mohþe, mouȝte, from Old English moþþe, mohþe, mohþa (“any destructive insect larva”), from Proto-West Germanic *moþþō, *mottō, from Proto-Germanic *muþþô, *muttô (“moth, worm”), from Proto-Indo-European *mutn-, *mut- (“worm”). Cognate with Saterland Frisian Motte (“moth”), West Frisian mot (“moth”), Dutch mot (“moth”), German Low German Motte, Mott (“moth”), German Motte (“moth”), Swedish mott (“moth”) and Norwegian Nynorsk mott (“moth”).
So that, dear lords, if I be left behind, / A moth of peace, and he go to the war, / The rites for which I love him are bereft me, / And I a heavy interim shall support / By his dear absence. Let me go with him.c. 1603–1604 (date written), William Shakespeare, “The Tragedie of Othello, the Moore of Venice”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act I, scene iii]:
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Dated A liver spot, especially an irregular or feathery one.
To remove moth patches, wash the spots with a solution of common bicarbonate of soda and water several times a day, until the patches are removed, which will usually be in forty-eight hours.1895, Good Housekeeping, page 196, ISSN: 0731-3462
Craves for sour things, chalks and eggs, fatty people with light brown spots on the face or liver spots, moth patches on forehead and cheek.1999, R. L. Gupta, Directory of Diseases & Cures: In Homoeopathy, →ISBN, page 254:
1 more example
There are signs of liver affections as weakness, yellow complexion, liver spots, and moth spot like a saddle over the nose.2005, J. D. Patil, Textbook of Applied Materia Medica, →ISBN, page 108: