These words mean "short-lived," "occurring or existing only briefly," "passing," "fleeting." Transitory is usually applied to events and situations; transient is applicable to people: "We are transient guests at this hotel, not permanent ones." "Going to parties is only a transitory pleasure." Transient, unlike transitory, can also be used as a noun."A temporary guest is a transient." Related adjectives include ephemeral, fugitive, fleeting, momentary, evanescent, provisional, and temporary.
Dictionary of problem words and expressions. Harry Shaw. 1975.