noun pl. helixes he′·lixes or helices hel′i·ces′ (hel′i sēz′)

1. any spiral, as one lying in a single plane or, esp., one moving around a right circular cone or cylinder at a constant angle, as a screw or bolt thread does
2. Anat. the folded rim of cartilage around the outer ear
3. Archit. an ornamental spiral, as a volute on a Corinthian or Ionic capital
4. Zool. any of a genus (Helix) of spiral-shelled land gastropods, including the common, edible European snail (H. pomatia)

Etymology: L, kind of ivy, spiral < Gr, a spiral < helissein, to turn around < IE base *wel-, to turn, twist > walk