know (something) by heart

(redirected from knew by heart)

know (something) by heart

To have learned or memorized something completely. Ask Becky to recite the poem—she knows it by heart. I can't sing that song in front of an audience if I don't know the words by heart!
See also: heart, know

know something by heart

Fig. to know something perfectly; to have memorized something perfectly. I know my speech by heart. I went over and over it until I knew it by heart.
See also: heart, know
References in classic literature ?
The other had worked at the laws of corporation, and knew by heart what every member of the corporation ought to know, so that he thought he could quite well speak on State matters and give his opinion.
He looked at it with a slight feeling of disappointment, but he had read till he knew by heart the jewelled words with which Walter Pater has added beauty to the most famous picture in the world; and these now he repeated to Miss Price.
Katharine knew by heart the sort of mood that possessed her as she walked upstairs to the drawing-room, her mother's arm in hers; and she could anticipate the pleasure with which, when she had turned on the lights, they both regarded the drawing-room, fresh swept and set in order for the last section of the day, with the red parrots swinging on the chintz curtains, and the arm-chairs warming in the blaze.
And we interpreted this as a sign, as powerless people tend to do, of heaven's willingness to let us have a few more minutes, to say what we have to say, to locate an address that we once knew by heart.
He knew by heart Max's threat to his mama, "I'll eat you up.
The hate song chosen by the girls, which they knew by heart, included the words, "I want to carry a machine gun and a rifle," and, "We shall strike Israel.
When Joel let the audience sing the final chorus of that last song, it was the perfect cap to an enjoyable evening of songs every one there knew by heart.