Well-known anti-cyberbullying activist Lizzie Velasquez has spoken out against a new mean meme that uses her image.

The image in the meme shows Ms Velasquez leaning against a tree, with the words: "Michael said he would meet me behind this tree for a bit of fun. He's running late, would someone please tag him and tell him I'm still waiting?"

In a Facebook post on Sunday (Dec 11) that has since garnered 117,000 likes and more than 92,000 shares, Ms Velasquez said she had "seen memes like this all over Facebook recently".

Saying that she was writing the post "not as someone who is a victim but as someone who is using their voice", she wrote that her post was "a reminder that the innocent people that are being put in these memes are probably up just as late scrolling through Facebook and feeling something that I wouldn't wish on my worst enemy".

"No matter what we look like or what size we are, at the end of the day we are all human," wrote the 27-year-old. "I ask that you keep that in mind the next time you see a viral meme of a random stranger. At the time you might find it hilarious but the human in the photo is probably feeling the exact opposite."

Online commenters flocked to show their support for Ms Velasquez, with many berating the Facebook pages that shared the meme.

Netizen Karisa Schmidt commented on Ms Velasquez's post: "I seen it, called them out, stood up for you and told them a piece of your story. They removed it. I'm so sorry that people are so cruel about something they know nothing about."

One of the pages that shared the meme appears to have been shut down.

Overwhelmed by the response, Ms Velasquez posted a video on Sunday thanking netizens for "their love and support".

"When you see something online, remember that there is a human that is being affected by it. So think before you tweet, think before you share, think before you like. Because we just want to be accepted," she said.

Ms Velasquez, who was once cyberbullied with the label The World's Ugliest Woman, was born with a rare condition that left her body unable to store fat. She has turned adversity into positivity by becoming a motivational speaker who has given TED talks and has a sizeable following on social media.

She also has Marfan syndrome, a genetic disorder that can affect a person's body shape and limbs.