Hel"i*coid (?), a. [Gr. ; , , spiral + shape: cf. F. h'elicoide. See Helix.]
1.
Spiral; curved, like the spire of a univalve shell.
2. Zool.
Shaped like a snail shell; pertaining to the Helicidae, or Snail family.
Helicoid parabola Math., the parabolic spiral.
© Webster 1913.
Hel"i*coid, n. Geom.
A warped surface which may be generated by a straight line moving in such a manner that every point of the line shall have a uniform motion in the direction of another fixed straight line, and at the same time a uniform angular motion about it.
© Webster 1913.