1. (noun) a colorless element that is one of the six inert gasses; occurs in trace amounts in air

• atomic number 36
• krypton

2. (noun) 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

• communist party of kampuchea
• khmer rouge
• party of democratic kampuchea

1. (noun) 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

• act of terrorism
• terrorism
• terrorist act

1. (noun) a colorless element that is one of the six inert gasses; occurs in trace amounts in air

• argonon
• inert gas
• noble gas
• chemical element
• element