Meanings
nouniris diaphragm (plural iris diaphragms)
plural iris diaphragms
- An adjustable diaphragm by which the diameter of an approximately circular opening may be controlled, as for regulating the aperture of a lens; it consists of a number of movable thin curved plates fastened at regular intervals around the inside of a ring, the positions of which are simultaneously adjusted by a single knob on the outside of the lens. It is used in cameras and microscopes.
Synonyms & antonyms
noundiaphragm consisting of thin overlapping plates that can be adjusted to change the diameter of a central opening
Similar
Also see
Synonym sets from Open English WordNet, CC BY 4.0.
Origin
Derives from its action which is reminiscent of the iris of the eye.
Full word history & related roots →Translations
German Irisblende
- Irisblendeadjustable diaphragm
Tagalog alikmata
- alikmataadjustable diaphragm
Cite this entry
APA
iris diaphragm. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/iris%20diaphragm
MLA
“iris diaphragm.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/iris%20diaphragm. Accessed November 4, 2026.
Chicago
WatkinsX Dictionary, s.v. “iris diaphragm,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/iris%20diaphragm.
Source: iris diaphragm on Wiktionary, CC BY-SA 4.0.