Unspecific ordinal number is a term used to describe a number that does not have a specific value, such as 'FIRST' or 'SECOND'. It is usually represented by the letters 'NTH', which stands for 'NTH order'. This term is commonly used in mathematics and computer science, where it is used to refer to an unspecified position in a sequence. In crossword puzzles, it is often used to represent a blank space, where the answer is unknown.