skull

American  

[skuhl] / skʌl /

noun

1. the bony framework of the head, enclosing the brain and supporting the face; the skeleton of the head.

2. the head as the center of knowledge and understanding; mind.

   to get literature's great ideas through our skulls.

3. Armor. the part of a helmet that covers the top of the head.

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idioms

1. out of one's skull, crazy; demented.

skull British  

/ skʌl /

noun

1. the bony skeleton of the head of vertebrates See cranium

2. derogatory the head regarded as the mind or intelligence

   to have a dense skull

3. a picture of a skull used to represent death or danger

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skull Scientific  

/ skŭl /

1. The part of the skeleton that forms the framework of the head, consisting of the bones of the cranium, which protect the brain, and the bones of the face.

2. See more at skeleton

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Other Word Forms

• skull-less adjective
• skull-like adjective

Etymology

Origin of skull

1175–1225; Middle English scolle < Old Norse skalli

Explanation

The bones of a person's or animal's head make up the skull. All vertebrates have a skull. Pirate flags often feature a human skull and crossbones (because a parrot skull wouldn’t be nearly so scary). The wide-eyed head of a skeleton is its skull. Skulls are hard and bony, but they're a little bit flexible as well—characteristics that help them protect the brain they enclose. Your skull consists of two parts: the bones of your face and the neurocranium, or "braincase." The precise origin of skull is uncertain, but it probably traces back to the Old English scealu, "husk or shell."

Example Sentences

The Nanotyrannus skull was first discovered in 1942 and initially classified as Gorgosaurus.

From Science Daily • Apr. 15, 2026

Brain-computer interfaces exist today, but many of them rely on drilling a hole in the skull and implanting a physical interface to allow the brain to communicate with external devices.

From The Wall Street Journal • Apr. 6, 2026

He and others have developed noninvasive interfaces, but these are clunky and uncomfortable, typically consisting of large skull caps with a mass of electrodes.

From The Wall Street Journal • Apr. 6, 2026

It is also the first fossil from the country to include parts of a dinosaur skull.

From Science Daily • Apr. 1, 2026

Then she covered the card with her hand and let her eyes roll upward alarmingly, until they nearly disappeared into her skull.

From "The Hidden Gallery" by Maryrose Wood

Related Words

• cranium
• scalp