Synonyms for Atomic Number 11 (same or very similar meaning)
WordNet sense 1 (a silvery soft waxy metallic element of the alkali metal group; occurs abundantly in natural compounds (especially in salt water); burns with a yellow flame and reacts violently in water; occurs in sea water and in the mineral halite (rock salt)):
sodium, NaFrom the ODE community, based on WordNetadd/edit