a title applied or assumed through custom, courtesy, or association and without regard for its being officially merited.
a title allowed by custom, as to the children of dukes.
Origin of courtesy title
First recorded in 1860–65
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
any of several titles having no legal significance, such as those borne by the children of peers
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