Grief is the noun, the deep sorrow itself, as in she shared her grief with friends. Grieve is the verb, the act of feeling that sorrow, as in she needed time to grieve. If the word follows the or an adjective, it is grief; if it follows to or a pronoun acting, it is grieve.
The core difference
Grief is the noun naming deep sorrow; grieve is the verb describing the act of feeling or causing that sorrow.
- grief — deep sorrow, especially caused by loss: He never fully worked through his grief over his father's death.
- grieve — to feel deep sorrow, especially after a loss: She is still grieving the end of her marriage.
How to tell them apart
The pair splits cleanly by part of speech: grief is always a noun, naming the sorrow itself, while grieve is always a verb, describing the action of feeling that sorrow. Both trace back to the same Latin root, gravis, meaning heavy, which also gives English the words grave and gravity, so all three carry a sense of weight.
Grief also has a lighter, informal sense meaning trouble or annoyance, as in noisy neighbours giving someone nothing but grief, which has nothing to do with bereavement. Grieve can likewise mean to cause someone distress, as in it grieves me to see the old house fall into ruin, so the verb is not limited to the person doing the mourning.
