tooorangey.DictionaryItemKeySearch

If you know the value of the dictionary item but not the key, you can search by value in the back office, use in conjunction with DictionaryDashboard package for Umbraco 6, to move dictionary editing, outside of Setting section

Umbraco 7 version is stand alone, and can be installed via Nuget: Install-Package tooorangey.uDictionaryItemSearch

More details on the following blog posts:

V6: http://tooorangey.co.uk/posts/yes-i-see-how-it-works-but-what-is-the-dictionary-item-called-that-i-need-to-edit/

v7: http://tooorangey.co.uk/posts/its-not-that-simple-this-dictionary-never-has-a-word-for-the-way-im-feeling/