- Learn English
-
Learn grammar
-
List of words
-
Study your cards
-
Hang On, Man!
-
Audio Books
-
More apps
- Recent searches
-
taking
-
rang
-
allhallows
-
auspicious
-
dismantle
-
politics
-
actinometer
-
virgin
-
evergreen state
-
actinometrical
- 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
