is an inanimate, shapeless mass (Pliny; Natural History, x. 64). This abortion was supposed to be produced by the influence of the moon. The primary meaning of calf is not the young of a cow, but the issue arising “from throwing out,” as a push, a protuberance; hence the calves of the legs.
“A false conception, called mola, i.e. moon-calf . . . a lump of flesh without shape or life.” —Holland: Pliny, vii. 16.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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