from
The Collaborative International Dictionary of English v.0.48
Thousandth \Thou"sandth\, a.
1. Next in order after nine hundred and ninty-nine; coming
last of a thousand successive individuals or units; -- the
ordinal of thousand; as, the thousandth part of a thing.
[1913 Webster]
2. Constituting, or being one of, a thousand equal parts into
which anything is divided; the tenth of a hundredth.
[1913 Webster]
3. Occurring as being one of, or the last one of, a very
great number; very small; minute; -- used hyperbolically;
as, to do a thing for the thousandth time.
[1913 Webster]