Mark-Room
Room for a boat to leave a mark on the required side. Also,
- room to sail to the mark when her proper course is to sail close to it, and
- room to round or pass the mark as necessary to sail the course without touching the mark.
However, mark-room for a boat does not include room to tack unless she is overlapped inside and to windward of the boat required to give mark-room and she would be fetching the mark after her tack.