o

Definitions

General English

Astronomy

  • (written as O)
    The hottest type of star, with surface temperatures of 30 000° to over 60 000°, so that almost all atoms at the surface are more or less heavily ionised. O type stars are rare because they have short lifetimes by comparison with the cooler members of the other spectral classes.

Slang

  • noun
    (written as O)
    opium, in the jargon of drug users

Sports

  • noun
    (written as O)
    a human blood type of the ABO system containing the O antigen. Someone with this type of blood can donate to all other types in the group but can receive only type O blood.

Business

  • symbol forOhm
    (written as O)

Agriculture

  • symbol forBelow Average
    (written as O)

Electronics

  • chemical symbol foroxygen
    (written as O)
  • symbol foroutput
    (written as O)
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