Evanescent
Part of speech: adjective
Definition: vanishing, disappearing, fleeting ephemeral, momentary barely there, almost imperceptible
Example sentence: If people want to be better writers, they can't just read the blogs! You've got to look at something that's outside this rushing world of evanescent words.
Temporary
Part of speech: adjective
Definition: For a limited time, ephemeral, not constant; transient
Part of speech: noun
Definition: One serving for a limited time; short-term employee.
Example sentence: It's better to enjoy life - selection is a temporary thing.