(inorganic chemistry) Any of the 14 radioactive elements of the periodic table that are positioned under the lanthanides, to which they have similar chemistry.

plural of actinide

(inorganic chemistry) Of or pertaining to the actinides. / (organic chemistry) Of or pertaining to actinidic acid or its derivatives.

(organic chemistry) A triterpene phytoalexin isolated from the peel of kiwi fruit (Actinidia deliciosa)