Webster's Revised Unabridged Dictionary · 1913

Sinistrously

Sinistrously (sin"is*trus*ly) , adverb

1.
In a sinistrous manner; perversely; wrongly; unluckily.
2.
With a tendency to use the left hand.
Many, in their infancy, are sinistrously disposed, and divers continue all their life left-handed. — Sir T. Browne