Wiktionary
a. scarce, or difficult to find.
Usage examples of "thin on the ground".
She allowed herself a moment longer to recall all she and Paul Tankersley had been to one another, and then she put the memory gently away once more and followed Andrew toward the range officer's counter to sign in.
Official Temple policy held there was no need to venture beyond Bethel when three centuries of valiant breeding left the Chosen still thin on the ground in the initial area of settlement.
Ratcats will be thin on the ground for a while, except for the ones stored in coldsleep.
The other girls would be upset, especially the young and not-so-experienced ones, the servants would be nursing bruised bodies and ill-tempers, and since by now the word had spread all up and down the Grand Canal that the Red Cat had been descended upon by the Schoppies in force, customers would be thin on the ground tonight.
At this time of the year the tourists were thin on the ground and there was not much of a crowd.