The state of being free from obstruction or interference.
The state of being free from obscurities or opacity; distinctness of light, colour etc.
Mental or sensory distinctness; clarity of understanding, perception etc.
Rapid and minimal: a whirlwind tour, a whirlwind romance.
A person or body of objects or events sweeping violently onward.
A violent windstorm of limited extent, as the tornado, characterized by an inward spiral motion of the air with an upward current in the center; a vortex of air. It usually has a rapid progressive motion.