Sinister

1. Inauspicious, ominous, unlucky, illegitimate (as in bar sinister).
2. Evil or seemingly evil; indicating lurking danger or harm.
3. (archaic) Of the left side. Antonym: dexter
4. (heraldry) On the left side of a shield from the wearer's standpoint, and the right side to the viewer. Antonym: dexter
5. (obsolete) Wrong, as springing from indirection or obliquity; perverse; dishonest.