/therr"tee ith/ , adj.
1. next after the twenty-ninth; being the ordinal number for 30.
2. being one of 30 equal parts.
n.
3. a thirtieth part, esp. of one ( 1 / 30 ).
4. the thirtieth member of a series.
[ bef. 900; THIRTY + -ETH 2 ; r. ME thrittythe, OE thritegtha ]