(dĭm′out′)n.1. Restricted use of lights at night, as to make a city less visible from the air in wartime.2. The semidarkness resulting from restricted use of lights at night.
dim-out
n (Military) (in the US) a restriction which limits the use of lights at night
dim′-out`
or dim′out`,
n. a reduction or concealment of night lighting, esp. in wartime to be less visible to an enemy. [1940–1945]Translations