noun py·ro·sphere \-ˌsfi(ə)r\

Definition of pyrosphere

  1. 1 :  the hot central portion of the earth

  2. 2 :  a hypothetical spherical zone of molten magma that is held to intervene between the crust of the earth and a solid nucleus and to supply lava to volcanoes

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Origin and Etymology of pyrosphere

International Scientific Vocabulary pyr- + sphere

Seen and Heard

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a rounded knoll or a ridge of ice

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