sun protection factor: the effectiveness of suntanning preparations in protecting the skin from the harmful effects of the sun's ultraviolet radiation, as rated on a scale of increasing protectiveness from 2 to 15 or sometimes higher.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for spf
sender policy framework: a mechanism designed to prevent an e-mail address being duplicated and used as a false address from which to send unsolicited e-mails
sun protection factor: an indicator of how effectively a sun cream, lotion, cosmetic, etc, protects the skin from the harmful rays of the sunSPF 25
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Medicine definitions for spf
sun protection factor
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.