v. To knowingly say that something is smaller or less important than it actually is.
the GNU version of the Collaborative International Dictionary of English
v. To make little or less in a moral sense; to speak of in a depreciatory or contemptuous way.
The Century Dictionary and Cyclopedia
To make small or smaller; reduce in proportion or extent.
To cause to appear small; depreciate; lower in character or importance; speak lightly or disparagingly of.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
v. lessen the authority, dignity, or reputation of
v. cause to seem less serious; play down
v. express a negative opinion of
Word Usage
"In this, great numbers of caves are hollowed out, and carvings are seen which suggest architectural forms, though on a scale so grand that architectural terms belittle them."