noun ·Rare ·Advanced level

Definitions

Noun

1. 1
   Dated form of protactinium. alt-of, dated, uncountable
2. 2
   a short-lived radioactive metallic element formed from uranium and disintegrating into actinium and then into lead wordnet

Synonyms

All synonyms

protactiniumatomic number 91paprotactinium

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