We found 18 dictionaries that define the word essential oils:

General (10 matching dictionaries)

1. essential oils: Merriam-Webster
2. essential oils: Collins English Dictionary
3. essential oils: Vocabulary.com
4. essential oils: Wordnik
5. essential oils: Cambridge Advanced Learner's Dictionary
6. essential oils: Wiktionary
7. Essential oils: Dictionary.com
8. Essential Oils (Midnight Oil album), Essential Oils (album), Essential oils: Wikipedia, the Free Encyclopedia
9. essential oils: FreeDictionary.org
10. essential oils: TheFreeDictionary.com

Business (2 matching dictionaries)

11. Construction Term Glossary (No longer online)
12. Glossary of Spa Terms (No longer online)

Computing (1 matching dictionary)

13. essential oils: Encyclopedia

Medicine (3 matching dictionaries)

14. essential oils: Merriam-Webster Medical Dictionary
15. online medical dictionary (No longer online)
16. essential oils: Medical dictionary

Science (1 matching dictionary)

17. Agricultural Thesaurus and Glossary (No longer online)

Tech (1 matching dictionary)

18. Candle Making Glossary (No longer online)

(Note: See essential_oil as well.)

Definitions from Wiktionary (essential oil) ▸ noun:  A volatile oil, used to make perfumes and flavourings, especially one having the characteristic odour of the plant from which it is obtained. ▸ Also see essential_oil Types: lavender, peppermint, tetree, lemon, eucalyptus, rosemary, clove, ginger, more... ▸ Words similar to essential oils ▸ Usage examples for essential oils ▸ Idioms related to essential oils ▸ Wikipedia articles (New!) ▸ Words that often appear near essential oils ▸ Rhymes of essential oils ▸ Invented words related to essential oils