noun Also show·boat·er (for defs 2, 3).
verb (used without object)
to perform or behave in an outrageous or spectacular manner.
Origin of showboat
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a paddle-wheel river steamer with a theatre and a repertory company
(intr) to perform or behave in a showy and flamboyant way
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
Online Etymology Dictionary, © 2010 Douglas Harper