What is the meaning of the word "ob"?

Definitions:

  1. In medical context, stands for Obstetrician or Obstetrics, the branch of medicine that deals with pregnancy, childbirth, and postpartum care. copy to clipboard ABBREVIATION
    • She went to her OB for a prenatal check-up. copy to clipboard
  2. In product codes or inventory lists, stands for "obsolete", meaning the item is no longer in production or use. copy to clipboard ABBREVIATION
    • The software versin is OB and unsupported. copy to clipboard
  3. In travel, aviation, and shipping contexts, is an abbreviation for "on board", used to indicate something or someone is on a vehicle, ship, or aircraft. copy to clipboard ABBREVIATION
    • The crew is already OB the vessel. copy to clipboard