iris diaphragm

noun

: an adjustable diaphragm of thin opaque plates that can be turned by a ring so as to change the diameter of a central opening usually to regulate the aperture of a lens

Word History

First Known Use

1867, in the meaning defined above

Time Traveler
The first known use of iris diaphragm was in 1867

Dictionary Entries Near iris diaphragm

iris borer

iris diaphragm

iris family

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Cite this Entry

“Iris diaphragm.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/iris%20diaphragm. Accessed 30 Nov. 2024.

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Kids Definition

iris diaphragm

noun
: an adjustable diaphragm of thin plates used for changing the diameter of a central opening to control the amount of light passing (as into a microscope or camera)

Medical Definition

iris diaphragm

noun
: an adjustable diaphragm of thin opaque plates that can be turned by a ring so as to change the diameter of a central opening usually to regulate the aperture of a lens (as in a microscope)
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