| Clue | Source | Date |
|---|---|---|
| O.R. activity, for short | ||
| OR activity: Abbr | Newsday | 25 Mar 2018 |
| OR activity | Wall Street Journal | 15 May 2015 |
| OR activity | ||
| Med. specialty | ||
| OR activity | ||
| Dr. in the OR | ||
| OR activity | ||
| Like some instruments: Abbr. | ||
| OR activity | ||
| O.R. doings | ||
| Certain M.D. | ||
| Medical man: Abbr. |