focal length

noun

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

Examples of focal length in a Sentence

Recent Examples on the Web Nikon hasn't released any F1.4 primes for the system, but has quality F1.8 glass in 20mm, 24mm, 35mm, 50mm, and 85mm focal lengths. PCMAG, 12 Sep. 2024 The Pro model will see 5x telephoto, with 120mm focal length that was only on the iPhone 15 Pro Max. Jonathan Limehouse, The Courier-Journal, 10 Sep. 2024 There are marks at 16mm, 23mm, 35mm, and 50mm to give you a visual indicator of the current focal length. PCMAG, 15 July 2024 Whereas those alternatives have telescoping barrels that extend to reach longer focal lengths, the XF 16-50mm has an internal zoom mechanism. PCMAG, 15 July 2024 See all Example Sentences for focal length 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'focal length.' 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

1682, in the meaning defined above

Time Traveler
The first known use of focal length was in 1682

Dictionary Entries Near focal length

Cite this Entry

“Focal length.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/focal%20length. Accessed 8 Oct. 2024.

Kids Definition

focal length

noun
: the distance of a focus from the surface of a lens or inwardly-curved mirror

Medical Definition

focal length

noun
: the distance of a focus from the surface of a lens or concave mirror
symbol f

More from Merriam-Webster on focal length

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