We found 2 dictionaries that define the word fossil oils:

General (2 matching dictionaries)

1. fossil oils: Merriam-Webster
2. fossil oils: Vocabulary.com

(Note: See fossil_oil as well.)

Definitions from Wiktionary (fossil oil) ▸ noun:  crude oil ▸ Also see fossil_oil ▸ Words similar to fossil oils ▸ Usage examples for fossil oils ▸ Idioms related to fossil oils ▸ Wikipedia articles (New!) ▸ Words that often appear near fossil oils ▸ Rhymes of fossil oils ▸ Invented words related to fossil oils