1
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Phrase(s): write something down
to make a note of something; to record something in writing. • Please write this down. • Please write down what I tell you.
McGrawhill's American Idioms And Phrasal Verbs
2
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1. Set down in writing, record, as in Please write down your new address and phone number. [Late 1500s] 2. Reduce in rank, value, or price, as in They've written down their assets. [Late 1800s] 3. Write in a simple or condescending style, as in These science texts are written down for high-school students. [Second half of 1800s]
American Heritage Idioms