a person that recently got a tumblr and doesn't understand the point. they are compared to cancer cells, which are useless and multiply rapidly. tumblr cancers are useless and go against the #1 rule of tumblr: DO NOT TELL YOU IRL FRIENDS.

they also use annoying terms like WHAT IS AIR and WHAT IS BREATHING, etc. and they try to fit in by writing in their bio that they are bisexual and atheist, because a lot of tumblr people actually are. they do not have open minds and they will unfollow you if you post an opinion they do not agree with.
they listen to Never Shout Never and think they are ~*~s3w iNdi3~*~

they have about 0-30 followers after a month, and they delete their tumblr when they don't understand why they are being hated on for not knowing what air is.

if you fit this definition, delete your tumblr and spare the rest of us.
tumblr cancer: *sees something funny* WHAT IS AIR??!!?!?!?!

real tumblr kid: loln.
by amy_wo0o0 November 8, 2010
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