pitch dark
[adjective]
Synonyms: black, atramentous, ebon, ebony, inky, jet, jetty, pitch-black, raven, sable

[TahlilGaran] English Synonym Dictionary ▲

ˌpitch-ˈdark adjective
completely dark:
Outside it was pitch-dark and pouring with rain.

[TahlilGaran] Dictionary of Contemporary English ▲

pitch-dark
very dark
It was pitch-dark when I took the garbage out to the garbage can.

[TahlilGaran] English Idioms Dictionary ▲

pitch dark
adj. Totally, completely dark.
A starless and moonless night in the country can be pitch dark.

[TahlilGaran] English Idioms Dictionary ▲