Metallica's 1991 album Metallica is commonly known by what nickname?

Metallica's 1991 album Metallica is commonly known as The Black Album.

The nickname comes from the record's stark, predominantly black artwork, which features a nearly invisible design of the band logo and a coiled snake. The official title is simply Metallica, matching the band's name.

The name helps distinguish this album from Metallica's broader catalog, especially because the band had previously used descriptive or stylized titles such as Master of Puppets and ...And Justice for All.

The Black Album became the standard informal name used by fans, critics, retailers, and reference works. It is not a separate release or an alternate official title printed as the album's main name.