Fortieth, smith, myth, maybe more.
Thirtieth.
The correct spelling for 30th is "thirtieth".
"not thirtieth." There really isn't a precise single-word antonym for it.
The thirtieth sultan of the Ottoman Empire was Mahmud II.
Thirtieth means being one of 30 equal parts. So one thirtieth is 1/30 and 1/30 as a decimal is 0.0333...
Thirtieth.
adjective
winscosin.
thirtieth
Thirtieth.
0.56666 repeating
The thirtieth week of calendar year 2011 starts on Monday July 25 and ends on Sunday July 31.