Aphotic

//eɪˈfəʊtɪk// adj

adj ·Rare ·Advanced level

Definitions

Adjective
  1. 1
    Having no light, especially no sunlight.
  2. 2
    Describing that part of deep lakes and oceans where less than one per cent of sunlight penetrates and where photosynthesis is not possible.

    "As experiment has shown that light waves capable of effecting chemical changes do not penetrate the water deeper than 400 meters and as the other conditions of assimilation are met above this line, it is proposed to distinguish a diaphanic region including the land and the water to a depth of 400 m. and inhabited by assimilating organisms and an aphotic region including the ocean and lakes below the assimilation-line and the dark caves of the crust, where plant life is impossible."

Adjective
  1. 1
    lacking light; especially not reached by sunlight wordnet

Synonyms

All synonyms

Antonyms

All antonyms

Example

More examples

"The aphotic, or “midnight,” zone exists in depths below 1,000 meters. Sunlight does not penetrate to these depths and the zone is bathed in darkness."

Etymology

From a- (prefix meaning ‘not; without; opposite of’) + photic.

Related phrases

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.