from The Century Dictionary.
- noun The straight cone of the young shell in the nautiloid cephalopods, the mature form of which may be either straight (orthoceracone) or curved.
Sorry, no etymologies found.
As I work a lot with sculpey, I learned for example from an accident with the model of an orthocone nautiloid that it can become extremely though when I is baked on higher temperatures.
BoarCroc James Gurney 2010