student asking question

What is "pet rock"? Is it a common word?

teacher

Native speaker’s answer

Rebecca

A "pet rock" is quite literally a rock that you keep as a pet. It was a joke, novelty gift created in the 70s. You would literally buy a rock and treat it as a pet. It is not a common phrase as the trend has faded. However, as this movie is set in that time period, they included it.

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