sun protection factor


: 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

Examples of sun protection factor in a Sentence

Recent Examples on the Web On top of that, it’s formulated with SPF 40, providing notable protection against the sun’s UV rays (this is the second highest sun protection factor of our winners). Jessie Quinn, Peoplemag, 12 Sep. 2023 Selecting a broad-spectrum sunscreen with a high sun protection factor (SPF) is essential. Chicago Tribune, 28 July 2023 Use one that offers broad-spectrum coverage to filter out both UVA and UVB rays and has a sun protection factor (SPF) of 30 or higher. Alyssa Hui Published, Verywell Health, 12 July 2023 That’s because the rating system for sunscreen products — better known as SPF (sun protection factor) — pertains only to a sunscreen’s effectiveness against UVB rays; UPF, on the other hand, gauges a fabric’s effectiveness at filtering both ultraviolet A (UVA) and ultraviolet B (UVB). Jen Ator, Travel + Leisure, 29 June 2023 The fabric also offers the benefit of a sun protection factor of UPF 50, which protects the skin from sun damage. Courtney Leiva, Peoplemag, 10 June 2023 Here are some tips for using sunscreen:9 Use a sunscreen with a sun protection factor (SPF) of 30 or higher. Reapply your sunscreen every two hours and after swimming or sweating. Leah Groth, Health, 24 Mar. 2023 All sunscreens and sunblocks come with an SPF (sun protection factor). Claire Gillespie, Health, 24 Mar. 2023 The researchers had about 80 people put SPF30 sunscreen or moisturizer with the same sun protection factor on their faces. Roni Dengler, Discover Magazine, 3 Apr. 2019 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'sun protection factor.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1968, in the meaning defined above

Time Traveler
The first known use of sun protection factor was in 1968

Dictionary Entries Near sun protection factor


sun protection factor


Cite this Entry

“Sun protection factor.” Dictionary, Merriam-Webster, Accessed 6 Dec. 2023.

Medical Definition

sun protection factor

: spf
Last Updated: - Updated example sentences
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