What is (a) An apparatus for projecting a powerful beam of light of approximately parallel rays, usually devised so that it can be swiveled about. (b) The beam of light projecting by this apparatus called?

searchlight — (a) An apparatus for projecting a powerful beam of light of approximately parallel rays, usually devised so that it can be swiveled about. (b) The beam of light projecting by this apparatus. (Webster's 1913.)

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