agility (n.) Look up agility at Dictionary.com
early 15c., "nimbleness, quickness," from Old French agilité (14c.), from Latin agilitatem (nominative agilitas) "mobility, nimbleness, quickness," from agilis "nimble, quick," from agere "to set in motion; keep in movement" (see act (n.)). Of mental swiftness from mid-15c.