placard
PLAK-ard
/ˈplækɑːrd/
A diamond-shaped sign mounted on vehicles or containers warning of hazardous materials inside; a public notice or poster.
In hazmat, specifically refers to standardized diamond placards (DOT/UN numbers) displayed on transport tankers.
The story behind the word. From Middle Dutch 'plakken' (to stick or paste up) and Old French 'plaquer' (to slap on). It referred to official posted decrees slapped onto town square walls.
Word relationships
- signboard: Signboard is general, whereas placard in public safety implies an official regulatory warning code.
- poster: Poster is decorative or promotional, while placard is informational or regulatory.
Commonly confused with
- badge: A badge is worn by a person for identification, whereas a placard is attached to vehicles or structures for hazard identification.
Word family
- placarding (noun): The act of affixing hazardous material warning signs.
Collocations
- hazmat placard
- warning placard
- display a placard
- placard requirements
Example sentences
- "The state trooper inspected the tanker truck to ensure the class 3 flammable liquid placard was clearly visible." Transportation safety inspection
- "Protesters carried placards demanding cleaner air near the industrial chemical plant." Public demonstration
Memory hook
PLAK-ard is PLACED like a card on a truck to warn people. Diamond warning sign on wheels.
When not to use
Do not use to describe small price tags or adhesive shipping labels.
Fun facts
- Hazmat placards use four distinct colors (Red=Flammable, Yellow=Oxidizer, White=Toxic, Blue=Water-reactive) with specific 4-digit UN numbers.
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