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Webster 1913 Edition
Geosynclinal
Geˊo-syn-cli′nal
,Noun.
[Gr.
γέα
, γῆ
, the earth + E. synclinal
.] (Geol.)
the downward bend or subsidence of the earth’s crust, which allows of the gradual accumulation of sediment, and hence forms the first step in the making of a mountain range; – opposed to geanticlinal.