An object the sailing instructions require a boat to leave on a specified side, a race committee vessel surrounded by navigable water from which the starting or finishing line extends, and an object intentionally attached to the object or vessel. However, an anchor line is not part of the mark.

A course a boat would choose in order to sail the course as quickly as possible in the absence of the other boats referred to in the rule using the term. A boat has no proper course before her starting signal.

The space a boat needs in the existing conditions, including space to comply with her obligations under the rules of Part 2 and rule 31, while manoeuvring promptly in a seamanlike way.