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focal length

noun

Simple Definition of focal length

  • : the distance from the surface of a lens to the point of focus (sense 3)

Source: Merriam-Webster's Learner's Dictionary

Full Definition of focal length

  1. :  the distance of a focus from the surface of a lens or curved mirror

1693

First Known Use of focal length

1693

Rhymes with focal length


Medical Dictionary

focal length

play
noun \-ˌleŋ(k)th\

Medical Definition of focal length

  1. :  the distance of a focus from the surface of a lens or concave mirror—symbol f




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