a gif that is used on a social media site such as tumblr to answer questions or remark on statements. they may or may not have words on them. multiple reaction gifs may be used to fulfill a single purpose.
I used a reaction gif of Katerina from The Vampire Diaries shaking her head to respond to a question on tumblr that I didn't like.
by savannamae October 26, 2011
Can you define these popular missing words?