Fleeting is used to describe something which lasts only for a very short time. 短暂的
adjective [原级] 短暂的，飞逝的
The girls caught only a fleeting glimpse of the driver. 姑娘们只是匆匆瞥了那个司机一眼。
verb [vt. 及物动词] <文>疾驰，飞逝；使（时间）飞快地过去；转瞬即逝（fleet 的过去式和过去分词）
Time is fleeting.; Time flies. 时光飞逝。
