We found 26 dictionaries that define the word mass number:

General (14 matching dictionaries)

1. mass number: Merriam-Webster
2. mass number: Oxford Learner's Dictionaries
3. mass number: American Heritage Dictionary of the English Language
4. mass number: Collins English Dictionary
5. mass number: Vocabulary.com
6. mass number: Wiktionary
7. mass number: The Wordsmyth English Dictionary-Thesaurus
8. mass number: Infoplease Dictionary
9. mass number: Dictionary.com
10. Mass number: Wikipedia, the Free Encyclopedia
11. mass number: Rhymezone
12. mass number: FreeDictionary.org
13. mass number: Mnemonic Dictionary
14. mass number: TheFreeDictionary.com

Business (1 matching dictionary)

15. mass number: Legal dictionary

Computing (1 matching dictionary)

16. mass number: Encyclopedia

Medicine (4 matching dictionaries)

17. mass number: Merriam-Webster Medical Dictionary
18. Dorland's Illustrated Medical Dictionary (No longer online)
19. online medical dictionary (No longer online)
20. mass number: Medical dictionary

Science (5 matching dictionaries)

21. Chemistry Dictionary (No longer online)
22. Mass Number: Extragalactic Astronomy
23. General Chemistry Online (No longer online)
24. Mass number: NRC Glossary of Nuclear Terms --
25. mass number: UNCChem Glossary

Tech (1 matching dictionary)

26. Explosives (No longer online)

(Note: See mass_numbers as well.)

Definitions from Wiktionary (mass number) ▸ noun:  (physics, physical chemistry) The total number of protons and neutrons in an atomic nucleus. Symbol: A Similar: nucleon number, atomic mass number, atomic mass, atomic number, neutron number, proton number, magic number, nuclide, atomic mass unit, mass defect, more... Opposite: atomic number, proton number Phrases: atomic mass number, more... Adjectives: electronuclear, negative, high-energy, pycnonuclear, internuclear, decinormal, weak, molal, unbound, coulombic, molar ▸ Words similar to mass number ▸ Usage examples for mass number ▸ Idioms related to mass number ▸ Wikipedia articles (New!) ▸ Words that often appear near mass number ▸ Rhymes of mass number ▸ Invented words related to mass number