To deliver a monologue.

Of or resembling a monolith. / Consisting of a single chunk of hard material rather than an assembly of discrete parts.

A black and white image, especially such a photograph. / (dated) A painting executed in shades of a single colour. / A ceramic glaze of a single colour; an object so glazed.

Having only one colour. / (photography) Representing colours with shades of gray.

(agriculture) The cultivation of a single crop at a time. / (anthropology) A culture or society that lacks diversity; a society marked by monoculturalism.

To cultivate such a crop

A person who is obsessed with a single thing, to the exclusion of other concerns.

Focused on one thing above all others.

A scholarly book or a treatise on a single subject or a group of related subjects, usually written by one person.

(transitive) To write a monograph on (a subject). / (transitive, US) Of the FDA: to publish a standard that authorizes the use of (a substance).