lighttight

/ˈlaɪtˌtaɪt/
adjective
  1. Designed to prevent any light from entering or escaping; completely sealed against light.
    • The darkroom door was lighttight, so no light could ruin the photographs.
    • The photographer used a lighttight bag to load film in bright sunlight.
    • The laboratory required lighttight containers to store light-sensitive chemicals.
Synonyms
Antonyms