Strong H8563 תַּמְרוּר tamrûr · bitterness

Jeremiah

1. Jeremiah 6:26
   O daughter of my people, gird thee with sackcloth, and wallow thyself in ashes: make thee mourning, as for an only son, most bitter lamentation: for the spoiler shall suddenly come upon us.
2. Jeremiah 31:15
   Thus saith the Lord; A voice was heard in Ramah, lamentation, and bitter weeping; Rahel weeping for her children refused to be comforted for her children, because they were not.