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sun protection factor

noun

Definition of sun protection factor

  1. :  a number assigned to a sunscreen that is the factor by which the time required for unprotected skin to become sunburned is increased when the sunscreen is used —abbreviation SPF

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First Known Use of sun protection factor

1978

Medical Dictionary

sun protection factor

noun

Medical Definition of sun protection factor

  1. :  spf

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sun protection factor

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