- Learn English
-
Learn grammar
-
List of words
-
Study your cards
-
Hang On, Man!
-
Audio Books
-
More apps
- Recent searches
-
acipenser
-
go back on
-
adagio
-
locust
-
interwind
-
enormous
-
die down
-
korean
-
pineapple
-
observer
- Hide translation
actinium
actinium /ækˈtɪnɪəm/
noun
-
A radioactive element of the actinide series; found in uranium ores
(
Ac
, actinium
, atomic number 89
)
a radioactive element of the actinide series; found in uranium ores
