(idiomatic) To do or experience something exceedingly difficult or rare.

(US) Standard form of all cats are grey in the dark.

(UK, sometimes vulgar and offensive) Sex is enjoyable regardless of the physical attractiveness or social station of one's partner.

(astronomy, physics) dark matter comprising elementary particles whose composition is as yet unknown, but is presumed to be unlike normal protons, neutrons and electrons etc.

(potentially vulgar and offensive, archaic) Synonym of all cats are grey in the dark: Sex is enjoyable regardless of the status, physical attractiveness, or social station of one's partner.

Alternative form of every cloud has a silver lining

Alternative form of better to light a single candle than to curse the darkness

Alternative form of better to light a single candle than to curse the darkness

Even in the face of hopelessness and discontent, it is more worthwhile to do some good, however small, in response, than to complain about the situation.

Alternative form of better to light a single candle than to curse the darkness