concealed; obscure; covert: hidden meaning; hidden hostility.
past participle of hide1.
Synonyms for hidden
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
concealed or obscureda hidden cave; a hidden meaning
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
past participle of hide (v.1); a Middle English formation (Old English had gehydd "hidden") on the model of ride/ridden, etc. Hidden persuaders (1957) was Vance Packard's term for "ad men."
Online Etymology Dictionary, © 2010 Douglas Harper