fairy godmother definition by American Heritage Dictionary
nounThe American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
A generous benefactor.
fairy godmother - Phrases/Idioms
A generous benefactor, as in An anonymous fairy godmother donated the money for the new organ. This expression alludes to a stock character in fairy tales such as Cinderella, who gives unexpected and much needed assistance. [Late 1800s]