IPA: /ˌdʒiːoʊˈsɪn.klaɪn/
KK: /ˈdʒiːoʊsɪnˌklaɪn/
A long, basin-shaped area near a continent where a lot of sediment and volcanic material has built up over time.
The geosyncline formed over millions of years, collecting layers of sediment.
Geosyncline is formed from "geo-" (meaning earth) and "syncline" (from Greek "synklinos", meaning to incline together). The term describes a large-scale depression in the Earth's crust where sediment accumulates, indicating a geological feature related to the Earth's structure.
Think of 'geo-' meaning earth and 'syncline' referring to layers that incline together, which helps you remember that a geosyncline is a geological feature where layers of earth are inclined together.