half-moon has definitions from the fields of anatomy,astronomy
1
[ noun ] (anatomy) the crescent-shaped area at the base of the human fingernail

Synonyms

lunule lunula

Used in print

(William C. Smith, "Why Fear Ideas?"...)

The son and heir of a prominent family marries a girl who has tell-tale shadows on the half-moons of her finger_nails .

Related terms

area nail

2
[ noun ] (astronomy) the time at which the moon is at first or last quarter when half its face is illuminated
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