The coordinate phrase means that there is no difference between words and they are equal to each other. Generally, coordinate phrases can be interchanged.
A meaningful description of the thoughts and feelings expressed by art forms, like a lingering sound, lasts for three days. It is also often used to express the aesthetic effect of works with high artistic quality. Profound means thorough and in-depth; Harsh and harsh. Depth is related to meaning and belongs to a coordinate phrase.