Minimize? Belittle?
To say that the Grand Canyon is nice is to understate its grandeur.
overstate
Disguise, belie, overstate, understate, conceal, misstate, falsify, exaggerate, con, etc. For more you could just type in "misrepresent" into Dictionary.com and click on the Thesaurus tab. Hope this helped. :)
Overstate, exaggerate.
overstate, magnify
yes
Unethical and illegal.
Depreciate, minimize or understate.
understate, mute, tone down, subdue
Downplaying the significance of an event or emotion.
Simply to avoid taxes
Military goods, underground economy and my as*hole