o

Meanings

Noun

• a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust
• the 15th letter of the Roman alphabet
• the blood group whose red cells carry neither the A nor B antigens
  • "people with type O blood are universal donors"

Synonyms

atomic number 8, group O, oxygen, type O