spher·oid (sfîr'oid', sfěr'-) n. A body that is shaped like a sphere but is not perfectly round, especially an ellipsoid that is generated by revolving an ellipse around one of its axes. sphe·roi'dal (-oid'l), sphe·roi'dic (-oi'dĭk) adj., sphe·roi'dal·ly adv., sphe'roi·dic'i·ty (-dĭs'ĭ-tē) n.