magma

/ˈmæɡmə/ (bre, ipa) · /ˈmæɡmə/ (ame, ipa) · /ˈmag-mə/ (ame, mw)

magma — noun

1. very hot, melted rock that lies deep under the ground; when it bursts out of a v

1.名詞B2
釋義

very hot, melted rock that lies deep under the ground; when it bursts out of a volcano onto the surface, it is then called lava.

例句

Geologists drilled through volcanic ash to study how magma moves beneath the Earth's surface.

subject collocation: geologists study magma

Pressure built up as magma rose slowly toward the crater of Mount Sakurajima.

collocation: magma rises / pressure builds

同義詞
  • molten rock

    plain-English equivalent; works in both technical and everyday writing

  • lava

    only after it reaches the surface; not interchangeable underground

用法筆記

Uncountable: say 'magma rises', not 'a magma rises'. Distinguish from 'lava' — same melted rock, but 'magma' stays underground while 'lava' has reached the surface.

常見錯誤

❌The volcano shot magma into the sky.
✅The volcano shot lava into the sky.
💡once melted rock leaves the volcano, it is called lava, not magma.
❌Several magmas filled the chamber.
✅Magma filled the chamber.
💡magma is uncountable; do not pluralise it.