adjective
fleeting
FLEE-ting/ˈfliːtɪŋ/
lasting only a very short time
The bubble's fleeting existence ends when it bursts moments after forming.

Etymology
The image is of something floating or drifting away. Through senses of swift movement and gliding away like a stream, fleeting came to describe something that lasts only briefly.
In context
it's also fleeting because of the speed at which the moon's shadow passes across earth's surface a total eclipse generally only lasts a few minutes
More examples
- We catch a fleeting glimpse of a deer through the trees.
- For a fleeting moment, I think I recognize his voice.
- The good news brings only fleeting relief from her worries.
Forms
fleeting · more fleeting · most fleeting
fleetingly adverb — For only a very short time.