We found 32 dictionaries that define the word arboretum:

General (24 matching dictionaries)

1. arboretum: Merriam-Webster
2. arboretum: Oxford Learner's Dictionaries
3. arboretum: American Heritage Dictionary of the English Language
4. arboretum: Collins English Dictionary
5. arboretum: Vocabulary.com
6. Arboretum, arboretum: Wordnik
7. arboretum: Wiktionary
8. arboretum: Webster's New World College Dictionary, 4th Ed.
9. arboretum: The Wordsmyth English Dictionary-Thesaurus
10. arboretum: Infoplease Dictionary
11. Arboretum, arboretum: Dictionary.com
12. arboretum: Online Etymology Dictionary
13. Arboretum (Derby ward), Arboretum (disambiguation), Arboretum: Wikipedia, the Free Encyclopedia
14. Arboretum: Online Plain Text English Dictionary
15. arboretum: Webster's Revised Unabridged, 1913 Edition
16. arboretum: Rhymezone
17. Arboretum: AllWords.com Multi-Lingual Dictionary
18. arboretum: FreeDictionary.org
19. arboretum: Mnemonic Dictionary
20. arboretum: TheFreeDictionary.com
21. arboretum: Longman Dictionary of Contemporary English
22. arboretum: Merriam-Webster

Business (1 matching dictionary)

23. Travel Industry Dictionary (No longer online)

Computing (1 matching dictionary)

24. arboretum: Encyclopedia

Medicine (1 matching dictionary)

25. online medical dictionary (No longer online)

Miscellaneous (1 matching dictionary)

26. arboretum: A Word A Day

Science (1 matching dictionary)

27. Botanical Terms (No longer online)

Slang (2 matching dictionaries)

28. The Arboretum: A Seattle Lexicon
29. arboretum: Urban Dictionary

Tech (1 matching dictionary)

30. Lake and Water Word Glossary (No longer online)

(Note: See arboreta as well.)

Definitions from Wiktionary ( ) ▸ noun:  A place where many varieties of tree are grown for research, educational, and ornamental purposes. Similar: botanical garden, arbor, arboret, fruticetum, pinetum, tree of life, botanic garden, arbor vitae, tree farm, orchard, more... Opposite: desert, wasteland, barren land Phrases: morris arboretum, United States National Arboretum, National Memorial Arboretum, Morton Arboretum, Arnold Arboretum, more... Adjectives: acre, national, new, small, local, famous, fine, extensive, beautiful, large, private Colors:     green,     brown,     olive,     forest green,     sage, more... ▸ Word origin ▸ Words similar to arboretum ▸ Usage examples for arboretum ▸ Idioms related to arboretum ▸ Wikipedia articles (New!) ▸ Popular adjectives describing arboretum ▸ Words that often appear near arboretum ▸ Rhymes of arboretum ▸ Invented words related to arboretum