actinide

noun

ac·​ti·​nide ˈak-tə-ˌnīd 

: any of the series of elements with increasing atomic numbers that begins with actinium or thorium and ends with lawrencium see Periodic Table

Examples of actinide in a Sentence

Recent Examples on the Web

Recycling these actinides into fresh fuel changes how engineers manage long-term radioactive waste. — Aman Tripathi, Interesting Engineering, 7 Aug. 2026

These extreme events could create the kind of neutron-rich environments needed to produce actinides, particularly in galaxies like the Gaia Sausage. — Victoria Corless, Space.com, 4 June 2025

After 200 years, the decay heat of HLW would be reduced by a factor of up to 30 in all minor actinide-burning schemes as compared to the reference PWR once- through scheme. — James Conca, Forbes, 27 Apr. 2021

Meant for studying actinides, the ROBL allows scientists to analyze the metals with an extremely close eye through spectroscopy. — David Grossman, Popular Mechanics, 22 Oct. 2019

Word History

Etymology

acti(nium) + (lantha)nide

First Known Use

1945, in the meaning defined above

Rhymes for actinide

• aldehyde
• alkoxide
• alongside
• amplified
• arsenide
• beautified
• biocide
• bisulphide
• butoxide
• calcified
• ceramide
• certified