• To paralyze or to make stiff or inactive, especially through fear or shock
  • To harden organic matter into a stone or stone-like substance


If you've ever visited an earth sciences museum or studied geology in school, you may have been lucky enough to have seen wood that has been petrified. Petrified wood has the shape and structure of a tree trunk, but feels as hard and smooth as polished stone. That's because these objects have actually become stone - with enough time and under the right conditions, their organic matter gets swept away by underground water and replaced with hard, often brightly colored minerals. In this way, what was once soft and living becomes rigid and inert.

Such fossilized wood represents the scientific meaning of petrify: in geology and biology, the term is used to describe the process by which any organic matter is hardened or replaced by inorganic material such as silica or calcium. In essence, this is a form of fossilization, a way in which dead organisms become preserved through natural means. However, in everyday conversation, you're much more likely to hear petrify used figuratively. In this sense, a person often becomes "hardened" or shocked into stillness by a surprising or incredible event. If you've ever been unlucky enough to have been paralyzed with fear, you've unfortunately experienced firsthand this meaning of petrify. Although this meaning is often used to describe a reaction to fear, anything that is extremely unexpected can petrify someone in their tracks.

While this specific usage of petrify is perhaps the most common, the word can really be used to describe anything that stiffens or solidifies something. Cold temperatures can petrify water into icicles, and an absorbing television show can virtually petrify you on the couch; so can a well-cast "Petrificus Totalus" spell from an accomplished wizard like Hermione. Ironically, petrify is fluid enough to cover a number of situations!

Example: Fast-moving, mineral-rich underground waters are necessary for wood to petrify.

Example: The sound of the vacuum always manages to petrify my dog in fright.

Example: An accident on the highway had caused the flow of traffic to petrify.


Don't get frozen by the origins of petrify - its etymology is actually fairly simple. The word stems from the Latin roots petra, which means "stone," and ficare, which is related to the action of "making so." These roots would influence the formation of the French verb pétrifier, a near-cognate which means "to harden into a stone-like state." The literal use of petrify is first recorded in English towards the end of the sixteenth century, with its figurative meaning of "frozen in shock" following a couple of centuries later.

Derivative Words

Petrified: The preterit form of the verb petrify describes a past action of paralyzing or solidifying. It can also serve as an adjective to describe something that is frozen, especially as a result of fright.

Example: The young women was absolutely petrified with terror by the spider on the ceiling.

Petrifying: This form is used to describe when something is currently solidifying, or as an adjective to describe something as causing shock or paralysis.

Example: The poor spider couldn't understand why the young woman found him so petrifying.

Petrifies: The present tense form of petrify is used when a singular, third-person subject hardens something.

Example: No matter how friendly the spider tries to look, he always petrifies the young woman.

Petrification: This noun refers to the process by which something becomes as solid or still as stone.

Example: The spider wondered if there was a way he could use his powers of petrification for good.

In Literature

From Aldous Huxley's Brave New World:

For a moment the khaki mob was silent, petrified, at the spectacle of this wanton sacrilege, with amazement and horror.

Here, petrified is used to describe the way in which a shocking action has brought an unruly crowd to stillness.


  • Petrify will paralyze with fear


Fear, Halloween, Stone, Wood

Bring out the linguist in you! What is your own interpretation of petrify. Did you use petrify in a game? Provide an example sentence or a literary quote.