Test Your Vocabulary

Take Our 10-Question Quiz

Name That Thing

Take our visual vocab quiz

Test Your Knowledge »

True or False?

A quick quiz about stuff worth knowing

Take It Now »

Join Us on FB & Twitter

Get the Word of the Day and More

Facebook | Twitter

protium


pro·ti·um

noun \ˈprōt-ē-əm, ˈprō-shē-\

Definition of PROTIUM

: the ordinary light hydrogen isotope of atomic mass 1

Learn More About PROTIUM