spiroid

== English == === Etymology === From Latin spiroïdes, from Ancient Greek Ancient Greek σπειροειδής (speiroeidḗs). By surface analysis, spire +‎ -oid. === Adjective === spiroid (comparative more spiroid, superlative most spiroid) (geometry) Resembling or having the form of a spiral or helix. === Noun === spiroid (plural spiroids) (geometry) A curve that resembles a spiral or helix.