Word Study
protium
WORDNET DICTIONARY
Noun protium has 1 sense
- protium(n = noun.plant) genus protium - genus of chiefly tropical American trees having fragrant wood and yielding gum elemi; Array is a kind of rosid dicot genus
is a member of burseraceae, family burseraceae, torchwood family
OXFORD DICTIONARY
protium, n. the ordinary isotope of hydrogen as distinct from heavy hydrogen (cf. DEUTERIUM, TRITIUM).
Etymology
mod.L f. PROTO- + -IUM
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