The term "fourth" refers to the ordinal number that indicates the position of something in a sequence, specifically the one that comes after the third. It is commonly used in various contexts, such as in counting, ranking, or organizing items. For example, in a race, the runner who finishes after the third place is said to finish fourth. In music, "fourth" can also refer to an interval between two notes. A perfect fourth is the distance between the first and fourth notes of a scale, such as in the C major scale, where C to F represents a perfect fourth. This interval is fundamental in harmony and chord construction.