bonnet

¹ American  

[bon-it] / ˈbɒn ɪt /

noun

1. a hat, usually tying under the chin and often framing the face, formerly much worn by women but now worn mostly by children.

2. Informal. any hat worn by women.

3. Chiefly Scot. a man's or boy's cap.

4. a bonnetlike headdress.

   an Indian war bonnet.

5. any of various hoods, covers, or protective devices.

6. a cowl, hood, or wind cap for a fireplace or chimney, to stabilize the draft.

7. the part of a valve casing through which the stem passes and that forms a guide and seal for the stem.

8. a chamber at the top of a hot-air furnace from which the leaders emerge.

9. Chiefly British. an automobile hood.

10. Nautical. a supplementary piece of canvas laced to the foot of a fore-and-aft sail, especially a jib, in light winds.

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verb (used with object)

1. to put a bonnet on.

Bonnet ² American  

[baw-ne] / bɔˈnɛ /

noun

1. Georges 1889–1973, French statesman.

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bonnet British  

/ ˈbɒnɪt /

noun

1. any of various hats worn, esp formerly, by women and girls, usually framing the face and tied with ribbons under the chin

2. Also called: bunnet. 

   1. a soft cloth cap

   2. formerly, a flat brimless cap worn by men

3. the hinged metal part of a motor vehicle body that provides access to the engine, or to the luggage space in a rear-engined vehicle

4. a cowl on a chimney

5. nautical a piece of sail laced to the foot of a foresail to give it greater area in light winds

6. (in the US and Canada) a headdress of feathers worn by some tribes of American Indians, esp formerly as a sign of war

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Bonnet Scientific  

/ bô-nĕ′ /

1. Swiss naturalist who discovered parthenogenesis when he observed that aphid eggs could develop without fertilization. Bonnet was also one of the first scientists to study photosynthesis.

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bonnet Idioms  

1. see bee in one's bonnet.

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Other Word Forms

• bonnetless adjective
• bonnetlike adjective

Etymology

Origin of bonnet

1375–1425; late Middle English bonet < Middle French; Old French bonet material from which hats are made, perhaps < Old Low Franconian *bunni something bound (< Germanic *bund-, noun derivative of *bind- bind; cf. bundle), with -et -et; compare Late Latin abonnis, obbonis ribbon forming part of a headdress < Germanic, with a prefix corresponding to Middle High German obe- above

Explanation

A bonnet is an old-fashioned hat that ties under the chin. Sometimes people dress babies up in frilly clothes and bonnets. A bonnet isn't stiff like many hats are — instead, it's made of soft fabric and has no brim. It was common during the 17th and 18th centuries for women to wear bonnets, to keep their hair tidy and protected from dust and sun when they were outdoors. Today, you're less likely to see a bonnet on a grown woman, unless she's a historical reenactor or acting in a play. The root of bonnet is the Scottish bonat, "brimless hat."

Example Sentences

It added it would have a long bonnet to give it a "torpedo-shaped form", drawing inspiration from the company's experimental cars of the 1920s, known as EX models, and the Art Deco era.

From BBC • Apr. 14, 2026

Witnesses contacted police after seeing the Mercedes with extensive front-end damage to it including a "crumpled bonnet".

From BBC • Apr. 14, 2026

Depending on your mood, you might continue with Royal Red shrimp served raw with dots of fermented Scotch bonnet pepper and a dusting of spiced red hibiscus flower.

From The Wall Street Journal • Jan. 30, 2026

Collier shared a photo to social media, wearing a sleep mask and bonnet on the House floor.

From Salon • Aug. 19, 2025

I asked, pulling one of Mrs. Wigginbottom’s rock-hard biscuits from under my bonnet.

From "The Detective's Assistant" by Kate Hannigan