MEIKO (メイコ) is a Japanese VOCALOID originally developed by Yamaha Corporation and distributed by Crypton Future Media, Inc.. Her VOCALOID3 update was developed and distributed by Crypton Future Media. She was initially released in November 2004 for the first VOCALOID engine. 

"MEIKO" comes directly from her voice provider's name, "Haigō Meiko."

MEIKO's codename was "HANAKO";[1] it likely came from "Yamada Hanako (山田花子)", a placeholder name for female characters, and the Japanese equivalent to "Jane Smith". "Megumi" was also a name considered during her development.[2]

She is often misnamed Sakine Meiko by fans. The name originates from the eponymous derivative character, depicted as herself in her younger days.

MEIKO's boxart hid the front of her red sleeveless jacket, making it difficult to tell what the design consists of. Due to this, there are many different designs, even for official artwork.[5] MEIKO has no official given age. In Maker Hikōshiki Hatsune Mix she is usually portrayed as a middle-aged woman, however KEI mentioned in a magazine interview that what he depicts in the comic is not official.[6]

Spurned on by the items held by Hatsune Miku and KAITO, it became popular to feature MEIKO with One Cup Ozeki (sake).