Petroleum
/pəˈtroʊ.li.əm/noun
A flammable liquid hydrocarbon found beneath the Earth's surface and used to make fuels and other products.
Did you know?The word was coined in learned Latin from petra “rock” + oleum “oil,” and it entered English through alchemical and scientific writing long before it became the fuel of the modern world.
Etymological Timeline
Proto-Indo-European
PIE
*pet-
“to spread, fall, or fly; later descendants developed senses connected to stone and rock”
Ancient Greek
Greek
πέτρα (pétra)
“rock, stone”
Latin
Latin
petra
“rock, stone”
Latin
Latin
oleum
“oil, olive oil”
Medieval Latin
Latin
petroleum
“rock oil; mineral oil”
16th Century
English
petroleum
“a naturally occurring mineral oil or bitumen-like substance”
Modern English
English
petroleum
“a flammable liquid hydrocarbon used chiefly as fuel and in chemical manufacture”
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