one of a class of the largest warships; a battleship, battle cruiser, or aircraft carrier.
Origin of capital ship
First recorded in 1680–90
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
one of the largest and most heavily armed ships in a naval fleet
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