American Heritage Dictionary
(7)
Century Dictionary
(5)
GNU Webster's 1913
(1)
WordNet
(6)
Elsewhere on the web
At the wide angle end of the zoom range there is significant barrel distortion, which is not uncommon in this class of camera.— DigitalCameraReview.com Digital Camera News and Reviews
I don't like hearing hiss or the distortion, which comes along with analogue recordings.— Big Picture Big Sound - Home Theater, HDTV, Movie Reviews
The time course and magnitude of this distortion are similar to the mislocalization found psychophysically in humans.— CiteULike: Everyone's library
This omission of "human shields" from a human rights analysis of any asymmetric combat adds to the overall distortion, and to HRW's highly misleading characterization of many aspects of the Gaza situation.— NGO Monitor Research

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 once a week.