The spirit of the time; the taste and outlook characteristic of a period or generation: It's easy to see how a student . . . in the 1940's could imbibe such notions. The Zeitgeist encouraged Philosopher-Kings (James Atlas).
ETYMOLOGY:
German : Zeit, time (from Middle High German zt, from Old High German; see d- in Appendix I) + Geist, spirit; see poltergeist.