harden one's heart
Feel no sympathy for, as in We can't afford to give them more; we'll just have to harden our hearts when they ask. [Late 1300s]
Words nearby harden one's heart
hardcore,
hardcover,
hardecanute,
harden,
harden off,
harden one's heart,
harden up,
hardenberg,
hardenbergia,
hardenburg,
hardened