English Reference
noun

crucible

n.
US /ˈkɹusəbəɫ/ UK /kɹˈuːsəbəl/ cru·cible UK spelling crucibles

  1. 01 C1 Advanced Technical Science

    a special cup or container used to heat chemicals or metals to very high temperatures without melting itself.

    a vessel made of heat-resistant material, such as ceramic or graphite, used for high-temperature chemical reactions or melting metals.

    Simple

    The chemist placed the sample in a ceramic crucible before putting it into the furnace.

    In context

    The technician carefully monitored the graphite crucible as the alloy reached its melting point, ensuring the structural integrity of the container remained intact.

    melting potvessel
  2. 02 C2 Proficiency Literary

    a very difficult experience that tests your character and changes you.

    a severe trial or ordeal in which different elements interact to produce something new or in which a person is refined by pressure.

    Simple

    The war was a crucible that turned the young soldiers into experienced leaders.

    In context

    The economic crisis served as a crucible for the new government, forcing them to abandon idealistic policies in favour of pragmatic survival.

  3. 03 C2 Proficiency Technical Science

    the bottom part of a large industrial furnace where the hottest heat is found.

    the hearth or lowest section of a blast furnace where molten metal collects.

    Simple

    Molten iron collected in the crucible at the base of the blast furnace.

    In context

    Engineers inspected the lining of the furnace crucible to ensure it could withstand the corrosive effects of the molten slag.

A new study, published in Antiquity , describes the discovery of the earliest brass-making crucibles in a southern Chinese workshop in Guangzhou, dated to the 9th–10th century A.D.

Phys.org· 14 Aug 2026

From Latin crucibulum (“night-lamp, metallurgic melting-pot”), apparently a derivative of crux (“cross”), perhaps by analogy to thūribulum (“censer”) and suffix -bulum, or from crucio (“to torment”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level C2 · Proficiency
Frequency Frequent
Updated