pet•roPronunciation: (pe'trō), [key]
of or pertaining to petroleum or the petroleum industry.
the federally owned petroleum industry.
a combining form meaning “rock,” “stone,” used in the formation of compound words: petrology. Also,petri-; esp. before a vowel,petr-.
a combining form meaning “petroleum,” “the extraction and export of petroleum,” used in the formation of compound words: petrochemistry; petropower.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.