Apparently that's a common (in government/Washington DC, anyway) scheduling acronym which stands for "remain overnight."
The globe-trotting secretary of state and globe-trotting former president each kept up frantic travel schedules, which meant they were often not in the same place at the same time — or even on the same continent. The calendars indicate where Hillary and Bill each spent the night: "RON," in Washington parlance, the acronym for "remain overnight."
On weekdays, the Clintons typically spent the evenings in their separate homes — Hillary in northwest Washington near her office at the State Department, and Bill in Chappaqua near his office in New York. But the Clintons spent a lot of time traveling the world. On March 17, 2010, the entry read: HRC RON En route Moscow/ WJC RON White Oak, FL. Other exotic RONs: HRC RON London, England/WJC RON Stockholm Sweden. HRC RON Abu Dhabi, UAE/WJC RON London, England. HRC RON Taj Palace Hotel, New Delhi, WJC RON Chappaqua, NY.
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