Oishii combines the Japanese word oishii, meaning delicious, with tacosu, a Japanised pronunciation of tacos, creating a short phrase that spread through meme soundboards and short video edits. Its appeal comes from the contrast between a sincere sounding compliment and the silliness of praising tacos in that style. Creators reuse it whenever food looks good, when a character reacts with over the top joy, or as an ironic stamp of approval for meals that probably do not deserve such praise.