harbor animosity

Translations
таить враждебность
He harbors animosity towards her for years.
Он таит враждебность к ней на протяжении многих лет.
Definitions
To hold or maintain feelings of hostility, resentment, or ill will towards someone or something, often kept hidden or unexpressed.
Words
animosity

noun
враждебность
harbor

verb
укрывать