ink

A pigment (or dye)-based fluid used for writing, printing etc.

A particular type, color or container of this fluid.

The black or dark-colored fluid ejected by squid, octopus etc, as a protective strategy.

Publicity.

Tattoo work.

Cheap red wine.

To apply ink to; to cover or smear with ink.

To sign (a contract or similar document).

To apply a tattoo to (someone).

(of a squid or octopus) to eject ink (sense 3)