Definition of memes:
(n) :
(Internet) Media, usually humorous, which is copied and circulated online with slight adaptations, such as basic pictures, video templates, etc.
(n) :
(Internet) A specific instance of a meme, such as an image macro or a video, often with humorous superimposed text.
(n) :
(originally) Any unit of (originally cultural) information, such as a practice or idea, that is transmitted verbally or by repeated action from one mind to another in a comparable way to the transmission of genes.
(n) :
(Internet) A work produced and shared in response to a prompt or suggestion within an online group.
(v) :
(intransitive, Internet slang) To create and use humorous memes.
(v) :
(transitive, Internet slang) To turn into a meme; to use a meme, especially to achieve a goal in real life.