Even though 11th, 12th, and 13th end in 1, 2, and 3, they still take “th” because of their special spelling and pronunciation: 11th, 12th, 13th (not 11st, 12nd, or 13rd)
The correct form is 11th, not 11st. This rule applies because ordinal numbers in English always end with the last two letters of the word written out fully. For example, “first” ends in “st,” “second” ends in “nd,” “third” ends in “rd,” and “ fourth ” ends in “th.”
Correct spelling, explanation: this ordinal number should be written as 11th because they don’t pronounce it with first at the end (which would then indicate -st suffix), but we pronounce it eleventh, so with -th at the end.
In English linguistics, 11th is an ordinal numeral used to signify the order or position, in this case, position 11. Let’s use an example of 11th (not 11nd) in a sentence: Sarah is currently 11th in her swimming trial race. What does this mean? It simply means that Sarah is in the eleventh position with 10 swimmers ahead of her.
11nd or 11th, which is correct? | Grammar | Compare it Versus
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