"discoverable by inquiry or critical examination," c. 1600, probably a back-formation from inscrutable (q.v.), as there seems to be no Latin *scrutabilis.
Entries linking to scrutable
inscrutable adj.
"that cannot be discovered by searching, mysterious," c. 1500, from Late Latin inscrutabilis, from in- "not, opposite of" (see in- (1)) + *scrutabilis, from scrutari "examine, ransack" (see scrutiny). Related: Inscrutably; inscrutableness.