from The Century Dictionary and Cyclopedia
- Pertaining to a member of the Italian and French family Cassini, which produced four generations of astronomers, 1625-1845. Also Cassinoid.
- a bicircular quartic curve, the locus of a point the product of whose distances from two fixed points is constant. The Cartesian equation is (x + y + a)—4ax = m. If m ⟨ a, the real curve consists of two ovals; if m ⟩ a, it consists of one; and if m = a, it becomes the lemniscate. Cassinians are curves of the eighth class (except the lemniscate, which is of the sixth), and have four stationary tangents on the absolute.
- n. A Cassinian oval.
Sorry, no etymologies found.
In each case the mollusc is a loose fit in its burrow, having ample room for rotation, but the aperture of the latter is what is known as a cassinian oval, and generally projects slightly above the surface of the coral.
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