A [[date pun]] for the Japanese word [i]niku[/i] (肉) "meat". It can be on the 29th of any month, or on February 9th (2/9), as the digits 2/9 are "ni"/"ku" in Japanese.

Meat is a euphemism for "excess flesh" in Japanese, and eating red meat is likewise depicted as an easy way to get fat quickly, so pictures of [[curvy]], [[plump]], and [[fat]] girls start appearing on these days in greater numbers, sometimes alongside actual [[meat]].

Alternatively, some artists consider "meat day" as a celebration of characters [i]with[/i] meat, in other words, [[muscular]].

h4. See Also
* [[good meat day]]
* [[date pun]]
肉の日