Om Nom Nom Nom is an onomatopoeic phrase used to indicate that someone is eating or that a food item is particularly delicious. The expression is often used to caption image macros that involve food or appear as if something is being eaten.
The expression originated with the character Cookie Monster from the children's television series Sesame Street, who was invented by the American puppeteer Jim Henson in 1966. When given a plate of cookies, the monster would ravenously devour them while repeating the phrase "om nom nom." The earliest known appearance of the phrase "om nom" online was submitted to the website Urban Dictionary on December 19th, 2004.
An onomatopoeic adjective based on the sound emitted when something is "oh so tasty" (either through hunger or flavorological value) that one gnaws through it without regard to cleanliness or etiquette. This sort of ravenous eating will often result in an "om nom nom nom" noise being emitted from the eater.
The earliest known usage of "nom nom" as a caption was used in a Lolcat image macro posted on the website ICanHasCheezburger on May 2nd, 2007. The image consisted of two photographs of a cat posing next to a birthday cake with the caption "nom nom nom / nooo it are my birthday" (shown below).
On August 6th, the domain for the single topic blog Omnomnomnom.com was registered, which featured image macros captioned with variations of the expression. In August of 2008, an update for the game Team Fortress 2 was released, which included a sandwich item that would cause the Heavy character to make an "om nom nom" noise (shown below).
On August 6th, the Tumblr blog "Domo Nom Nom" was launched, featuring images of the character Domo eating various objects (shown below). On April 9th, the domain for the site Omnomnom.org was registered, allowing users to upload their own image macros using the phrase.
On February 27th, 2009, Parry Gripp, the lead singer of pop punk band Nerf Herder, uploaded a video featuring footage of different pet animals accompanied by the song "Nom Nom Nom Nom Nom Nom Nom" (shown below). Within four years, the video accumulated over 19.3 million views.