supersonic Antonyms

subsonic as slow as molasses in january slow procrastinatory negligent long-drawn loitering leisurely interminable inert indolent inactive imperceptible impeded sluggish snail-like transonic time-consuming sonic slow-moving draggy Lange laboured marathon waddling trudging toddling tardy idle hindered cumbersome creeping crawling conservative comfortable claudicant belated behindhand behind backward apathetic acoustical dawdling dead delayed heavy halted gradual gentle easy