obscuration

== English == === Etymology === From Latin obscūrātiō. By surface analysis, obscure +‎ -ation. === Noun === obscuration (countable and uncountable, plural obscurations) The state of being obscured. A unit of measurement used in particular for smoke detectors which respond to absorption of light by smoke, in percent absorption per unit length, e.g. % obs/ft, % obs/m. ==== Derived terms ==== ==== Related terms ==== ==== Translations ==== === References ===