Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Medical
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

iris diaphragm

noun

Definition of iris diaphragm

  1. :  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



Illustration of iris diaphragm

1867

First Known Use of iris diaphragm

1867


Medical Dictionary

iris diaphragm

noun

Medical Definition of iris diaphragm

  1. :  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)




Learn More about iris diaphragm

  1. Medical Dictionary: Definition of "iris diaphragm"


Seen and Heard

What made you want to look up iris diaphragm? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

February 9, 2016

marked by high spirits and laughter

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

image1037863653

Which of the following refers to thin, bending ice, or to the act of running over such ice?

pince-nez spindrift duvet kittly-benders
Name That Thing

10 quick questions: hear them, spell them, and see how your skills compare to the crowd.

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ