V. S. O.
(of brandy) very superior old.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
very superior old: used to indicate that a brandy, port, etc, is between 12 and 17 years old
(in Britain) Voluntary Service Overseas: an organization that sends young volunteers to use and teach their skills in developing countries
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