object lesson

American  

noun

1. a practical or concrete illustration of a principle.

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object lesson British  

noun

1. a convincing demonstration of some principle or ideal

2. (esp formerly) a lesson in which a material object forms the basis of the teaching and is available to be inspected

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Etymology

Origin of object lesson

First recorded in 1825–35

Example Sentences

He and his representatives are now threatening Cuba, Mexico, Colombia, Iran and Greenland, with Venezuela serving as an object lesson of what may happen if a country dares to disobey his wishes.

From Salon

But as curling moved from the prairies to the cities, the object lessons the sport taught changed as well.

From Los Angeles Times

“But it’s also an object lesson in what you can do if you’re solvent — and clever — during the worst recession in Southern California since the 1930s.”

From Los Angeles Times

Industry insiders have told the BBC that Fishwick is now regarded as an object lesson in how not to run an installation project.

From BBC

He gave a television interview that was so legendarily awful it’s become an object lesson in how not to start a campaign.

From Los Angeles Times