"lump of earth or clay," Old English clod- (in clodhamer "the fieldfare," a kind of thrush), from Proto-Germanic *kludda-, from PIE *gleu- (see clay).
Synonymous with collateral clot until the meanings differentiated 18c. Meaning "person" ("mere lump of earth") is from 1590s; that of "blockhead, dolt, stupid fellow" is from c. 1600 (compare clodpate, clodpoll, etc. in the same sense). It also was a verb in Middle English, meaning both "to coagulate, form into clods" and "to break up clods after plowing."
Old English clud "mass of rock, hill," related to clod.
The modern sense "rain-cloud, mass of evaporated water visible and suspended in the sky" is a metaphoric extension that begins to appear c. 1300 in southern texts, based on similarity of cumulus clouds and rock masses. The usual Old English word for "cloud" was weolcan (see welkin). In Middle English, skie also originally meant "cloud." The last entry for cloud in the original rock mass sense in Middle English Compendium is from c. 1475.
The four fundamental types of cloud classification (cirrus, cumulus, stratus, nimbus) were proposed by British amateur meteorologist Luke Howard (1772-1864) in 1802.
Meaning "cloud-like mass of smoke or dust" is from late 14c. Figuratively, as something that obscures, darkens, threatens, or casts a shadow, from c. 1300; hence under a cloud (c. 1500). In the clouds "removed from earthly things; obscure, fanciful, unreal" is from 1640s. Cloud-compeller translates (poetically) Greek nephelegereta, a Homeric epithet of Zeus.
Old English cnoll "hilltop, small hill, clod, ball," related to Old Norse knollr "hilltop;" German knolle "clod, lump;" Dutch knol "turnip," nol "a hill."
genus of fungi, Modern Latin, from Greek pilos "felt" (see pileated) + bōlos "a clod, clump."
1967, American English, from Yiddish klots "clumsy person, blockhead," literally "block, lump," from Middle High German klotz "lump, ball." Compare German klotz "boor, clod," literally "wooden block" (see clot (n.)).
late 14c., "soil of the earth; cultivated land;" also "a piece of land forming part of a clergyman's benefice," from Old French glebe, from Latin gleba, glaeba "clod, lump of earth," possibly from a PIE *glem- or *glom-, which might mean "contain, embrace" or "ball," or might be two different roots. Possible cognates include Old English clamm "a tie, fetter;" Old High German klamma "trap, gorge;" Old Irish glomar "gag, curb;" Latin globus "sphere," gleba, glaeba "clod, lump of earth;" Old English clyppan "to embrace;" Lithuanian glėbys "armful," globti "to embrace, support."
"fritter," 1827, from French beignet "fritter, egg-roll, doughnut" (14c.), from Old French buigne "bump, lump," from Frankish or some other Germanic source (compare Middle High German bunge "clod, lump"), or from Gaulish *bunia (compare Gaelic bonnach).