noun
also reversed spectrum line
: a strong line in an emission spectrum that has a dark line down its middle due to absorption by the colder vapor which surrounds the central luminous vapor
noun
also reversed spectrum line
: a strong line in an emission spectrum that has a dark line down its middle due to absorption by the colder vapor which surrounds the central luminous vapor
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012