"an overlapping of edges" (as of roof tiles, etc.), 1640s, from French imbrication, noun of action from stem of Latin imbricare "to cover with tiles," from imbricem (nominative imbrex) "curved roof tile used to draw off rain," from imber (genitive imbris) "rain, heavy rain; rainwater," from PIE *ombh-ro- "rain" (source also of Sanskrit abhra "cloud, thunder-cloud, rainy weather," Greek ombros "rain, a shower"), from root *nebh- "moist; water" (see nebula).
word-forming element meaning "high," sometimes also alto- (in cloud names, etc.), from Latin altus "high," literally "grown tall," from PIE root *al- (2) "to grow, nourish."
"a low layer of cloud," 1803, from Latin stratus "a spreading," from noun use of past participle of sternere "to spread out, lay down, stretch out," from nasalized form of PIE root *stere- "to spread."
"skewbald, of mixed colors," early 15c., skued, skeued, a word of uncertain origin. It is said to be not from skew (v.), but Klein's sources say it is and Middle English Compendium offers that as a possibility; OED suggests it is perhaps from Old French escu "shield," but also notes a close resemblance in form and sense with Icelandic skjottr, "the history of which is equally obscure." Watkins says it is Scandinavian and akin to Old Norse sky "cloud" on the resemblance of the markings to cloud cover.
word-forming element meaning "breast," from Latin mamma "breast" (which is cognate with mamma). The form mammato-, used in cloud terminology in reference to smooth, rounded shapes, is from Latin mammatus.
visible discharge of energy between cloud and cloud or cloud and ground, late Old English, "lightning, flash of lightning," verbal noun from lightnen "make bright," or else an extended form of Old English lihting, from leht (see light (n.)). The Old English word also meant "dawn, daybreak," and in Middle English "light of the sun, intense brightness, brilliance; the radiance of Christ." Another Middle English word for it was leven (mid-13c.), of uncertain origin, with no apparent source in Old English. (Old English had ligetung "lightning," from liget "lightning, flash of lightning." "Lightning" also was a specialized sense of lihting "lighting" and beorhtnes "brightness.")
Meaning "cheap, raw whiskey" is attested from 1781, also sometimes "gin." Lightning bug "firefly, phosphorescent beetle" is attested from 1778. Lightning rod from 1790.
1754, "cloudiness, haziness," from French nébulosité, from Late Latin nebulositatem (nominative nebulositas), from Latin nebulosus, from nebula "mist, vapor" (from PIE root *nebh- "cloud"). From 1761 as "faint, misty appearance surrounding certain stars."
"slight or delicate degree of difference in expression, feeling, opinion, etc.," 1781, from French nuance "slight difference, shade of color" (17c.), from nuer "to shade," from nue "cloud," from Gallo-Roman *nuba, from Latin nubes "a cloud, mist, vapor," from PIE *sneudh- "fog" (source also of Avestan snaoda "clouds," Latin obnubere "to veil," Welsh nudd "fog," Greek nython, in Hesychius "dark, dusky").
According to Klein, the French secondary sense is a reference to "the different colors of the clouds." In reference to color or tone, "a slight variation in shade," by 1852; of music, by 1841 as a French term in English.