Word
calcium carbonate
Uncountable noun
Definition
n. a white, solid substance found in rocks like limestone and marble, as well as in shells and bones. You often see it used in things like chalk, health supplements, or building materials.
n. a chemical compound with the formula CaCO3, occurring naturally as limestone, marble, and chalk. It is a common substance in the shells of marine organisms and serves as a major component of agricultural lime and antacid medications.
Examples
“Chalk is mostly made of calcium carbonate.”
“The white cliffs are composed primarily of calcium carbonate formed from the skeletal remains of tiny sea creatures.”
“In marine biology, the rising acidity of the oceans is a major concern because it prevents many organisms from effectively secreting calcium carbonate to build their shells.”
Examples
simple
“Chalk is mostly made of calcium carbonate.”
contextual
“The white cliffs are composed primarily of calcium carbonate formed from the skeletal remains of tiny sea creatures.”
complex
“In marine biology, the rising acidity of the oceans is a major concern because it prevents many organisms from effectively secreting calcium carbonate to build their shells.”
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.C1 AdvancedIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.7.0–8.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 5.0–5.595–113TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.945–990
- Level
- C1 · Advanced
- Updated
- アルファベット
- 読み方の一覧 →
QR code
englishreference.com/q/calcium-carbonate