geosynclinal (plural geosynclinals)
- (geology) The downward bend or subsidence of the Earth's crust, which permits the gradual accumulation of sediment and hence forms the first step in the formation of a mountain range.
Part or all of this entry has been imported from the 1913 edition of Webster’s Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.
(See the entry for geosynclinal in Webster’s Revised Unabridged Dictionary, G. & C. Merriam, 1913.)