Celerity (Latin celeritas) may refer to: Speed, quickness Speed of light, celeritas Celerity BBS, a computer bulletin board system popular in the 1990s Celerity Computing Inc., defunct San Diego, California vendor Celerity IT, a Virginia-based web development consulting group The phase velocity, speed of propagation of a wave Proper velocity, an alternative way of measuring motion in relativity USS Celeritas (SP-665), a United States Navy patrol vessel Mirage Celerity, an American two-seat cabin monoplane Celerity (carriage) See also Celery Celebrity Celer (disambiguation)