The definition of celerity is a very fast motion.
An example of celerity is movement of one hundred miles per hour.
swiftness in acting or moving; speed
Origin of celerityFrench célérité ; from Classical Latin celeritas ; from celer, swift: see hold
Swiftness of action or motion; speed. See Synonyms at haste.
Origin of celerityFrench célérité, from Old French, from Latin celerit&amacron;s, from celer, swift.
From Old French celeritee (compare French célérité), from Latin celeritas, from celer (“fast, swift”).