cis·​soid | \ ˈsiˌsȯid\
plural -s

Definition of cissoid

: a plane curve with two branches meeting at a cusp at one end of a diameter of a fixed circle, each point of the cissoid being obtained by going from the cusp along any chord to its intersection when extended with the tangent diametrically opposite the cusp and then returning along the extended chord a distance equal to the length of the chord

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Other Words from cissoid

cissoidal \ (ˈ)si¦sȯidᵊl \ adjective

History and Etymology for cissoid

Late Greek kissoeidēs, from Greek, like ivy, from kissos ivy + -oeidēs -oid

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