the additional dimension by which a solid object is distinguished from a planar projection of itself or from any planar object.
something that heightens the reality, vividness, or significance of a factual account, sequence of happenings, etc.: The illustrations added a third dimension to the story.
Origin of third dimension
First recorded in 1855–60
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
the additional dimension by which a solid object may be distinguished from a two-dimensional drawing or picture of it or from any planar object
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