lituus
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- đường xoắn ốc "giây"
Định nghĩa tiếng Anh
n. A curved staff used by the augurs in quartering the\n heavens.\nn. An instrument of martial music; a kind of trumpet of a\n somewhat curved form and shrill note.\nn. A spiral whose polar equation is r2/ = a; that is, a curve\n the square of whose radius vector varies inversely as the angle which\n the radius vector makes with a given line.