cissoid

[ sis-oid ]

noun

, Geometry.

1. a curve having a cusp at the origin and a point of inflection at infinity. Equation: r = 2 a sin(θ)tan(θ).

cissoid

/ ˈsɪsɔɪd /

noun

1. a geometric curve whose two branches meet in a cusp at the origin and are asymptotic to a line parallel to the y -axis. Its equation is y ²(2a – x ) =x ³ where 2a is the distance between the y -axis and this line

adjective

1. contained between the concave sides of two intersecting curves Compare sistroid

Other Words From

• cis·soidal adjective

Word History and Origins

Origin of cissoid¹

1650–60; < Greek kissoeidḗs, equivalent to kiss ( ós ) ivy + -oeidēs -oid

Word History and Origins

Origin of cissoid¹

C17: from Greek kissoeidēs, literally: ivy-shaped, from kissos ivy