Sinistral :: Sinistral (a.) Of or pertaining to the left, inclining to the left; sinistrous; -- opposed to dextral..
Sinistral :: Sinistral (a.) Having the whorls of the spire revolving or rising to the left; reversed; -- said of certain spiral shells.
Sinistrally :: Sinistrally (adv.) Toward the left; in a sinistral manner.