An ink, invisible on application or soon thereafter, that can later be rendered visible by some process, such as exposing it to heat. / An ink used in pranks that is visible at first but soon disappears.

To write, especially professionally.

(typography) A sharp recess in an inward corner, present in certain typefaces; when printed, ink fills them (as opposed to having normal corners, resulting in bleeding and loss of crispness).

plural of ink trap

(slang, intransitive) To write, especially to make a living.

(idiomatic) To receive publicity.

plural of ink well

A bottle of ink, especially one which a pen may be dipped into; inkwell.

(slang) A writer, especially of low-quality writing. / (slang) A tattooist.

(zoology) A muscular bag found in certain cephalopods used to generate ink.