The word "洗礼" is formed by combining the character "洗", meaning "to wash" or "cleanse", with the character "礼", meaning "ritual" or "ceremony". This juxtaposition results in a literal meaning of "washing ritual", which specifically refers to the religious rite of baptism, where water is used for symbolic purification. The formation directly merges the action of cleansing with the formal context of a ritual to convey this concept.