Ir

1 of 3

symbol

iridium

IR

2 of 3

abbreviation

1
information retrieval
2
infrared
3
British inland revenue
4
intelligence ratio
5
internal revenue

ir-

3 of 3

prefix

see in-

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Cite this Entry

“Ir.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Ir. Accessed 4 Nov. 2025.

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Kids Definition

ir-

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Medical Definition

Ir

1 of 2 symbol
iridium

IR

2 of 2 abbreviation
infrared

More from Merriam-Webster on Ir

Britannica.com: Encyclopedia article about Ir

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