- 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 celeritās, from celer, swift.