noun ·Rare ·Advanced level

Definitions

Noun

1. 1
   A rare stable isotope of calcium, ⁴⁶₂₀Ca, with 20 protons and 26 neutrons; it amounts to only 0.004% of the element in nature uncountable

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.