We found 25 dictionaries that define the word weightlessness:

General (16 matching dictionaries)

1. weightlessness: Merriam-Webster
2. weightlessness: Oxford Learner's Dictionaries
3. weightlessness: Collins English Dictionary
4. weightlessness: Vocabulary.com
5. Weightlessness, weightlessness: Wordnik
6. weightlessness: Cambridge Advanced Learner's Dictionary
7. weightlessness: Wiktionary
8. weightlessness: Dictionary.com
9. weightlessness: Cambridge Essential American English Dictionary
10. Weightlessness: Wikipedia, the Free Encyclopedia
11. weightlessness: Rhymezone
12. weightlessness: FreeDictionary.org
13. weightlessness: Mnemonic Dictionary
14. weightlessness: TheFreeDictionary.com

Business (1 matching dictionary)

15. weightlessness: Legal dictionary

Computing (1 matching dictionary)

16. weightlessness: Encyclopedia

Medicine (4 matching dictionaries)

17. weightlessness: Merriam-Webster Medical Dictionary
18. Medical Dictionary (No longer online)
19. online medical dictionary (No longer online)
20. weightlessness: Medical dictionary

Science (2 matching dictionaries)

21. From Stargazers to Starships Glossary (No longer online)
22. WEIGHTLESSNESS: Zoom Astronomy Glossary

Tech (1 matching dictionary)

23. AUTOMOTIVE TERMS (No longer online)

(Note: See weightless as well.)

Definitions from Wiktionary (weightlessness) ▸ noun:  (uncountable) The state of being free from the effects of gravity (the force). ▸ noun:  (countable) An experience or instance of being weightless. Similar: lightness, gravitylessness, zero gravity, forcelessness, chargelessness, masslessness, figurelessness, freefall, causelessness, unencumberedness, more... Opposite: gravity Phrases: weightlessness simulation, weightlessness countermeasures, more... Adjectives: simulated, apparent, near, true, term, complete, relative, own, prolonged, sudden, total ▸ Words similar to weightlessness ▸ Usage examples for weightlessness ▸ Idioms related to weightlessness ▸ Wikipedia articles (New!) ▸ Popular adjectives describing weightlessness ▸ Words that often appear near weightlessness ▸ Rhymes of weightlessness ▸ Invented words related to weightlessness