American Heritage Dictionary
(4)
Century Dictionary
(1)
GNU Webster's 1913
(1)
WordNet
(1)
Elsewhere on the web
It's insulting frankly, and the only reason why these forked tongued reporters agreed to write such effluvium is so that they can really sink their teeth into some real Met bashing stories down the line.— MetsBlog.com
It's too broadly parodic of too many things: the trivialization of abortion, modern art's fascination with effluvium, amoral academic culture justified as a form of faux-profound "consciousness-raising," etc etc etc.— The Jawa Report

American Heritage Dictionary (1)
Century Dictionary (1)
Bubble size: how much this word was used in a year
Bubble height: used more or less than expected, vs. all uses evenly distributed
You can expect to see this word about twice a year.