a small amount of air, smoke, etc. that is blown from somewhere （烟、气等的）一缕，少量
a puff of wind
一丝清风
Puffs of white smoke came from the chimney.
烟囱冒出了袅袅白烟。
Any chance of success seemed to vanish in a puff of smoke (= to disappear quickly).
成功的机会犹如一缕青烟，瞬息即逝。