helicline

1. (now uncommon, architecture) A curving or spiral-shaped ramp; (especially) the ramp at the 1939 New York World's Fair Theme Center.Examples: "A bridge will link the sphere to the tower, while from the latter a ramp 900 ft. long will slope gently to the ground curving around the fountain basis beneath the sphere in a huge three-quarter circle. This ramp is described as the “helicline,” and will be 50 ft. high at the top"; "We have heard rumours of several good buildings at the Fair, but the newscuttings have not so far found time to tell us about them among attractions so sensational that no previously known words would cover them. “Democracity” is studded with Trylons and Perispheres, slides on Heliclines and sploshes in Aquacades."; "Stepping to the helicline of the flood-lighted Perisphere at the New York World's Fair at midnight Sunday, an Army bugler sounded taps, signalizing the beginning of an epic grand finale."uncommon