noun. ['ˈæktɪˌnaɪd'] any of a series of radioactive elements with atomic numbers 89 through 103.
- -ide (English)
- actin- (English)
Rhymes with Actinide
Sentences with actinide
1. Noun, singular or mass
Americium, another actinide element, is slightly denser than mercury at 13.84 grams per cubic centimeter.
The lanthanide and actinide make up the f-orbitals.