moon calf
(also written without space between the words: ‘mooncalf’; plural: ‘moon calves‘; for the pronunciation, please click here)

[a mooncalf — a deformed still born (foetus) of a cow]
‘Mooncalf’ is a name given to a foetus which is not completely formed, dead or deformed and is sent out of the mother, usually of cows, and sometimes of women, used mostly in former times. The farmers in those days believed that the moon was responsible for an abortion of a cow and, eventually, that has been used for women, too. And also, because the dead or deformed baby (foetus) looks horrible, the monsters, which are supposed to look horrible, were/are called mooncalves.
( ‘foetus’ = the baby that is growing in the bag-like part inside a woman, or any mammal, called ‘womb’)

mooncalf/monster
a monster : any animal or animal-like creature (= living being) that is very huge, unusual, ugly, frightening, cruel, harmful, usually with animal and human body parts, imaginary, legendary or mentioned in the mythology
For an article that shows us how we come across this word in our browsing, please click here, for an article about mooncalf that shows us how this word/phrase is used in video games and blogs, please click here.

a mooncalf/an idiot
Figures of Speech:
moon calf (noun) = a born fool; an idiot by birth; an incompetent person
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