What do you call the path of actual travel when using a compass?

The term that best describes the path of actual travel when using a compass is "heading." Heading refers specifically to the direction in which a vessel or diver is pointing at any given moment as determined by the compass. This can change frequently, especially in conditions where a diver might be adjusting their position or if current and drift are factors.

While "course" refers to the intended path of travel over the ground, heading is focused more on the immediate angle in relation to north as indicated by the compass. This distinction is crucial for navigational accuracy, as the heading may not always align with the course due to external influences affecting movement.

"Direction" is a broader term that indicates orientation (such as north, south, east, or west) but does not specifically relate to the actual travel path. Similarly, "navigation" encompasses the overall process of planning and directing travel but does not specifically indicate the immediate angle or direction indicated by a compass. Therefore, "heading" is the most precise term related to the designations provided in the question.