What it means
Written in capitals, OR means the operating room (called the operating theatre in some countries). Surgical units speak of the time a client goes "to the OR" and of "OR staff". It is only read this way in capitals; the ordinary word "or" is not an abbreviation. In research articles and statistics, OR stands for odds ratio, a measure of risk.
In a chart
"Consent signed, client to OR at 0730."
Related terms
perioperative
Relating to the whole time around a surgery: before, during and after it.
operating room
A room in a hospital or surgery center that is specially set up and kept for performing surgery.
intraoperative
Happening during surgery, from when the client is brought into the operating room until they are moved to recovery.