trochoidal

enUK

tro·choid

T0374000 (trō′koid′, trŏk′oid′)n. A curve traced by a point on or connected with a circle as the circle rolls along a fixed straight line.adj. also tro·choi·dal (trō-koid′l, trŏk-oid′l)1. Capable of or exhibiting rotation about a central axis.2. Permitting rotation, as a pulley or pivot.
[Greek trokhoeidēs, wheellike : trokhos, wheel; see trochee + -oeidēs, -oid.]
tro·choi′dal·ly adv.