etiolated

adjective4

1. •
   Of a plant or part of a plant: pale and weak because of sunlight deprivation or excessive exposure to sunlight.

   • Seedlings are elongated and have closed cotyledons in the dark (aetiolated) while the hypocotyls are short and the cotyledons are open in the light (de-aetiolated). — 2007
2. •
   Of a plant: intentionally grown in the dark.
3. •
   Of an animal or person: having an ashen or pale appearance; also, haggard or thin; physically weak.

   • Birds inhabiting desert regions have an etiolated appearance.
4. •
   (figurative) Lacking in vigour; anemic, feeble.