Usually used in UK.
If you know something by heart, you can remember all the words in it without any help.
Learned in such a way that you can repeat it from memory.
We learned long passages of poetry off by heart.
by Dudu2805 February 3, 2019
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To learn something and keep it in mind for a longer time.

Synonyms:
To memorize
To learn by heart
Andy knows that it isn't easy for him to know anything off by heart.
by SmokingSkull January 21, 2011
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