actinic focus

noun

: the focus at which the chemically most effective rays as distinguished from the visually most effective are brought together (as by a lens)

called also chemical focus

Word History

First Known Use

1853, in the meaning defined above

Time Traveler
The first known use of actinic focus was in 1853

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Dictionary Entries Near actinic focus

Cite this Entry

“Actinic focus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/actinic%20focus. Accessed 18 Apr. 2024.

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