English Dictionary

On the left hand, or the side of the left hand; left; -- opposed to dexter, or right.
Source : opted (141928)  - auto

Unlucky; inauspicious; disastrous; injurious; evil; -- the left being usually regarded as the unlucky side; as, sinister influences.
Source : opted (141929)  - auto

Wrong, as springing from indirection or obliquity; perverse; dishonest; corrupt; as, sinister aims.
Source : opted (141930)  - auto

Indicative of lurking evil or harm; boding covert danger; as, a sinister countenance.
Source : opted (141931)  - auto