(transitive) To shade, cloud, or darken. / (transitive) To block light or radio transmission from. / (espionage) To secretly or discreetly track or follow another, to keep under surveillance.

Unofficial, informal, unauthorized, but acting as though it were. / Having power or influence, but not widely known or recognized.

(uncountable) Darkness where light, particularly sunlight, is blocked. / (countable) Something that blocks light, particularly in a window.

(transitive) To shield (someone or something) from light. / (intransitive, rare) To shield oneself from light. / (transitive) To alter slightly.

Abounding in shades. / Causing shade. / Overspread with shade; sheltered from the glare of light or sultry heat. / (informal) Not trustworthy; disreputable. / (UK, slang) Mean, cruel.

A diorama

(boxing, martial arts) To practice moves without an actual opponent, often in front of a mirror. / (figuratively) Argue with an imaginary enemy.

a senior group of opposition politicians who shadow the members of the government

Makeup that is applied to the eyelids and below the eyes to give a darker complexion there.

In shadow; darkened by shadows. / (of character) Dark, obscure. / (figuratively) Vague, dim, unclear, faint of an image. / (rare, dated) Indulging in fancies; daydreaming.