- Learn English
-
Learn grammar
-
List of words
-
Study your cards
-
Hang On, Man!
-
Audio Books
-
More apps
- Recent searches
-
au pair
-
cups
-
fo
-
active capital
-
unequal
-
unplugging
-
space-reflection symmetry
-
inability
-
underscores
-
culprits
- Hide translation
actinide
actinide /ˈækˈtɪnˌaɪd/
noun
-
Any of a series of radioactive elements with atomic numbers 89 through 103
(
actinide
, actinoid
, actinon
)
any of a series of radioactive elements with atomic numbers 89 through 103