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Webster 1913 Edition
Introgression
Inˊtro-gres′sion
,Noun.
[L.
introgressus
, p. p. of introgredi
to go in; intro-
within + gradi
to step, go.] The act of going in; entrance.
Blount.
Webster 1828 Edition
Introgression
INTROGRES'SION
,Noun.