The act of adding someones tweet
to your favorites on Twitter
. This is used as a form of appreciation when someone makes a good tweet
Also known as "Starring" due to the icon used to add something as a favorite.
There are websites that catalogue and rank tweets based on amount of stars given. This was initially started to record and rank funny tweets on sites such as Favrd.com and favotter.matope.com.
The much broader Favstar.fm was the first to use the non-dictionary term favorited deliberately.