Thir"teenth` (?), a. [From Thirteen: cf. AS. reoteoa.]
1.
Next in order after the twelfth; the third after the tenth; -- the ordinal of thirteen; as, the thirteenth day of the month.
2.
Constituting or being one of thirteen equal parts into which anything is divided.
© Webster 1913.
Thir"teenth`, n.
1.
The quotient of a unit divided by thirteen; one of thirteen equal parts into which anything is divided.
2.
The next in order after the twelfth.
3. Mus.
The interval comprising an octave and a sixth.
© Webster 1913.