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principal section

noun
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Definition of principal section

1 : a plane passing through the optical axis of a crystal specifically : the principal plane that contains either the wave normal or the ray of light under discussion
2 : a plane perpendicular to the edge of an optical prism

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Dictionary Entries Near principal section

principal ray

principal section

principal sum

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Cite this Entry

“Principal section.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/principal%20section. Accessed 24 May. 2022.

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