petr-

combining form

variants or petri- or petro-

1

a

: stone : rock

petrescent

Petricola

petrogenesis

b

: petroleum

petroporphyrins

2

: of or relating to the petrous portion of the temporal bone and

petrohyoid

Word History

Etymology

Middle French petr-, petri- & Latin petr- & New Latin petro-, from Greek petr-, petro-, from petros stone & petra rock

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Kids Definition

petr-

combining form

variants or petri- or petro-

1

: stone : rock

2

: petroleum

petrochemical

Etymology

Greek petros "stone" and petra "rock"