An "upgrade" to a product or service, which, while intended to be an enhancement or improvement, actually renders that product or service less useful or valuable than it previously was.
The word can be used as a noun. Its verb form is "to dehance". Its adjective form is "dehanced" (see below).
The most common example of dehancements are in the software industry. For example, the 2008 edition of Microsoft Word was dehanced. It is more difficult to navigate through screens and commands, and in general much less effective than earlier versions.
A sight threatening eye problem effecting one out of every 10,000 people. This serious condition can be treated with surgery or by leaving your basement and getting off of Tumblr.
My retinal detachment doesnt keep me from finding all the creppyiest memes and hotdog leg pics.