Dictionary.com
Thesaurus.com

godfather offer

British  

noun

  1. informal a takeover bid pitched so high that the management of the target company is unable to dissuade shareholders from accepting it

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of godfather offer

C20: from the 1972 film The Godfather, in which a character was made an offer he could not refuse by a threatening mafioso