noun
or tinker's dam
Etymology: tinker's damn probably so called from the tinkers' reputation for blasphemy; tinker's dam probably by folk etymology from tinker's damn; probably from the use by tinkers of a small dam of dough or mud to confine solder used in patching holes in pans
: something absolutely worthless
people who didn't give a tinker's damn about poetry were … interested — James Blish
pointed out a federal system isn't worth a tinker's damn — H.J.Laski
is too involved … to make us care a tinker's dam what happens — R.B.Morris