learn (something) by heart

learn (something) by heart

To learn something very thoroughly; to memorize something. Ask Becky to recite the poem—she learned it by heart. You don't have to learn these principles by heart, we just want you to have a basic understanding of them.
See also: by, heart, learn

learn something by heart

Fig. to learn something so well that it can be written or recited without thinking; to memorize something. The director told me to learn my speech by heart. I had to go over it many times before I learned it by heart.
See also: by, heart, learn

learn by heart

Also, learn by rote. See under by heart.
See also: by, heart, learn