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from The American Heritage® Dictionary of the English Language, 4th Edition

  • Rock; stone: petroglyph.
  • Petroleum: petrochemistry.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • of or pertaining to stone
  • of or pertaining to petroleum-based products
  • Pertaining to, or funded by, oil export

from the GNU version of the Collaborative International Dictionary of English

  • A combining form from Gr. pe`tra a rock, pe`tros a stone.


Greek, from petros, stone.
(American Heritage® Dictionary of the English Language, Fourth Edition)



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