twenty-oneth

twenty-oneth (not comparable)

1. (nonstandard) twenty-first

twenty-oneth (plural twenty-oneths)

1. (nonstandard) A fractional part of twenty-one, a twenty-first
   • 1844, “VI. New London Association.”, in Minutes of the General Association of Connecticut, at their Meeting in New London: June, 1844., page Appendix, p. 32:

     average ministerial age of pastors 22 years and nineteen twenty-oneths; average pastoral age, 13 years and ten twenty-oneths

• twenty-first