Correct spelling

53rd

Correct spelling, explanation: this form is correct, because there is an ending rd, which also occurs in the word-form third (in this case fifty-third). Therefore ordinal form for 53 is 53rd. Ending th is typical for ordinal numbers ending with this sound, therefore 53th is incorrect and 53rd is the correct form.

Definition of 53rd:
numeral, ordinal number between 52nd and 54th
We bought my dad a motorbike for his 53rd birthday.
It’s 53rd day since I’ve stopped smoking and I’m feeling great!


Incorrect spelling

53th

Incorrect spelling, explanation: this is an incorrect form because th is not the right ending for ordinal number third. For third and every other number ending with third the ending is rd, so here 53rd is the correct form. 53th is incorrect as it is using wrong ending. The only correct form is 53rd.

Incorrect spelling

53st

Incorrect spelling

Incorrect spelling

53nd

Incorrect spelling