succès fou

suc·cès fou

 (sük-sĕ′ fo͞o′)
n.
A wild success.

[French : succès, success + fou, mad.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

succès fou

(syksɛ fu)
n, pl succès fous (syksɛ fu)
a fantastic success
[literally: mad success]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014