A lolcat (pronounced /ˈlɒlkæt/ LOL-kat), or LOLcat, is an image macro of one or more cats. The image's text is often idiosyncratic and (intentionally) grammatically incorrect, and is known as lolspeak.

Lolcat is a compound word of the acronymic abbreviation LOL (laugh out loud) and the word "cat". A synonym for lolcat is cat macro or cat meme, since the images are a type of image macro and also a well-known genre of meme. Lolcats are commonly designed for photo sharing imageboards and other Internet forums.