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Webster 1913 Edition
Sinistrorsal
Sinˊis-tror′sal
,Adj.
[L.
sinistrorsus
, sinistroversus
, turned toward the left side; sinister
left + vertere
, vortere
, versum
, vorsum
, to turn.] Rising spirally from right to left (of the spectator); sinistrorse.
Webster 1828 Edition
Sinistrorsal
SINISTROR'SAL
,Adj.