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Webster 1913 Edition
Prophylactical
{
, Prophˊy-lac′tic
,Prophˊy-lac′tic-al
}Adj.
[Gr. [GREEK], fr. [GREEK] to guard against; [GREEK] before + [GREEK] to guard: cf. F.
prophylactique
.] (Med.)
Defending or preserving from disease; preventive.
Coxe.