An ordinal number is simply a number that represents position or order. However, there are several synonyms that can be used to refer to an ordinal number, depending on the context and the language. Some of the most commonly used synonyms for ordinal numbers include serial number, cardinal number, numeric designation, positional number, ordinal numeral, and place value. Each of these synonyms carries a slightly different connotation or meaning, so it is important to choose the right term depending on the intended use. For instance, while serial number implies a sequence of items, place value refers to the position of a digit in a number. Ultimately, the choice of synonym will depend on the specific context and the intended message.