undeterred - to be undeterred by sth.

contrary of deter (v.)
1570s, "discourage and stop by fear," from Latin deterrere "to frighten from, discourage from," from de "away" (see de-) + terrere "frighten, fill with fear" (see terrible). Meaning "stop or prevent from acting or proceeding by any countervailing motive" is from 1590s. Related: Deterred; deterring.