The word "潮汐" is formed by combining two characters: "潮" meaning tide, specifically the rising tide, composed of the water radical (氵) indicating its association with water and the component "朝" which suggests morning or direction; and "汐" meaning tide, specifically the ebb tide, composed of the water radical (氵) and the component "夕" meaning evening. Together, they represent the cyclical tidal movements of water.