Actinoid in a sentence as a noun

But this is very much not the case with landfill, in which the lanthanoids are conveniently separated not only from one another but from the hazardous actinoids — although cigarette-lighter flints have many lanthanoids, if you're mining catalytic converters, they'll be entirely free of both thorium and lanthanum.

Actinoid definitions

noun

any of a series of radioactive elements with atomic numbers 89 through 103

See also: actinide actinon

adjective

having a radial form; "starfish are actinoid--that is, they are radially symmetrical"