Lasting for only a very short time; passing swiftly and quickly. 'Fleeting' describes something that is transient and ephemeral, leaving little or no lasting impression.
It emphasizes the brevity and momentary nature of an experience, sensation, or object. A fleeting moment may be beautiful or significant, but its defining characteristic is its short duration.
The word often carries a sense of something almost being gone before one can fully grasp or appreciate it.
SHORT BRIEF
TEMPORAL FUGITIVE
TRANSIENT EPHEMERAL MOMENTARY
EVANESCENT TRANSITORY
MOMENTANEOUS