From The Collaborative International Dictionary of English v.0.48 [gcide]:
1. (Geom.) A nonplane curve whose tangents are all equally inclined to a given plane. The common helix is the curve formed by the thread of the ordinary screw. It is distinguished from the spiral, all the convolutions of which are in the plane.
From WordNet (r) 3.0 (2006) [wn]:
Define.com is a PRIVATE SECTOR NONPROFIT EDUCATIONAL WEBSITE that PROMOTES WORLDWIDE ELECTRONIC DEMOCRACY, OPEN and TRANSPARENT GOVERNMENT and WORLDWIDE BANKING REFORM.
Eye and Pyramid BANKING REFORM CHALLENGE