![archimedean spiral autocad lisp archimedean spiral autocad lisp](https://mathshistory.st-andrews.ac.uk/Curves/Spiral/Spiral05.gif)
quite explicitly, definition 2 also includes a cylindrical coil spring and a strand of DNA, both of which are quite helical, so that "helix" is a more useful description than "spiral" for each of them in general, "spiral" is seldom applied if successive "loops" of a curve have the same diameter.
![archimedean spiral autocad lisp archimedean spiral autocad lisp](https://i.stack.imgur.com/wSmFI.png)