We found 24 dictionaries that define the word protactinium:

General (16 matching dictionaries)

1. protactinium: Merriam-Webster
2. protactinium: Oxford Learner's Dictionaries
3. protactinium: American Heritage Dictionary of the English Language
4. protactinium: Collins English Dictionary
5. protactinium: Vocabulary.com
6. protactinium: Wordnik
7. protactinium: Wiktionary
8. protactinium: Webster's New World College Dictionary, 4th Ed.
9. protactinium: The Wordsmyth English Dictionary-Thesaurus
10. protactinium: Infoplease Dictionary
11. protactinium: Dictionary.com
12. Protactinium: Wikipedia, the Free Encyclopedia
13. protactinium: Rhymezone
14. protactinium: FreeDictionary.org
15. protactinium: Mnemonic Dictionary
16. protactinium: TheFreeDictionary.com

Business (1 matching dictionary)

17. protactinium: Financial dictionary

Computing (1 matching dictionary)

18. protactinium: Encyclopedia

Medicine (5 matching dictionaries)

19. protactinium: Merriam-Webster Medical Dictionary
20. Dorland's Illustrated Medical Dictionary (No longer online)
21. Medical Dictionary (No longer online)
22. online medical dictionary (No longer online)
23. protactinium: Medical dictionary

Science (1 matching dictionary)

24. Protactinium, protactinium: WebElements Periodic Table of the Elements

Definitions from Wiktionary (protactinium) ▸ noun:  A chemical element (symbol Pa) with atomic number 91: a dense, silvery-gray actinide metal. Similar: pa, atomic number 91, protoactinium, actinium, eka-protactinium, palladium, actinide, plutonium, uranium, praseodymium, more... ▸ Words similar to protactinium ▸ Usage examples for protactinium ▸ Idioms related to protactinium ▸ Wikipedia articles (New!) ▸ Popular adjectives describing protactinium ▸ Words that often appear near protactinium ▸ Rhymes of protactinium ▸ Invented words related to protactinium