- barium sulphate, barium sulfate, blanc fixe - a white insoluble radiopaque powder used as a pigment
--1 is a kind of sulfate, sulphate
- heavy spar, barite, barytes, barium sulphate - a white or colorless mineral (BaSO4); the main source of barium
--2 is a kind of mineral
--2 has substances: barium, Ba, atomic number 56