What does 'ddth' return in date formats?

In date formats, 'ddth' is used to format a date such that it represents the day of the month along with an English ordinal suffix — specifically, "th," "st," "nd," or "rd," depending on the number. This means that if you were to input a date like the 23rd of the month, 'ddth' would correctly format it to display as "23rd." This specific formatting is useful for creating more readable and conventional date representations in outputs.

The other interpretations do not apply to 'ddth'. For example, the number of the day of the year or the number of the day within the week are represented differently and would not affix ordinal indicators. Additionally, while you could format days using a different convention for displaying only the name of the day, 'ddth' specifically indicates that it is appending an ordinal suffix to the numeric day of the month.