Apical impulse is the place in the chest where the heartbeat can be palpated. The usual location depends on the morphological type of the person. In a normolineal individual, it is located at the intersection of the 4th or 5th left intercostal space with the left midclavicular line. This point corresponds to the area where the heart is closest to the costal grid thus allowing its palpation in an intercostal space. Usually lasts half of systole.
When relaying the details of what happened in a conflict or when trying to solve it, it is best and most helpful when people are informed of the specifics as to not miss any vital details that might impact the decision or resolution.