Noun kr has 2 senses
- krypton, Kr, atomic number 36 - a colorless element that is one of the six inert gasses; occurs in trace amounts in air
--1 is a kind of chemical element, element; noble gas, inert gas, argonon
--1 is a substance of air
- Khmer Rouge, KR, Party of Democratic Kampuchea, Communist Party of Kampuchea - a communist organization formed in Cambodia in 1970; became a terrorist organization in 1975 when it captured Phnom Penh and created a government that killed an estimated three million people; was defeated by Vietnamese troops but remained active until 1999
--2 is a kind of terrorist organization, terrorist group, foreign terrorist organization, FTO
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