The Hebrew noun laanah refers to wormwood, a bitter plant (Artemisia), and metaphorically to bitterness, poison, and grief. Occurring 8 times in the OT, it is used to describe the bitter consequences of sin, the anguish of God's judgment, and the poisoned path of the wicked.
In Scripture, laanah (wormwood) is the taste of God's judgment — the bitterness that follows when covenant is broken. Jeremiah links wormwood to God's judgment on Israel (Jeremiah 9:15; 23:15). Proverbs warns that the adulteress's lips drip honey, but her end is bitter as laanah (5:4). This word vividly communicates the doctrine of consequences: sin has a pleasant taste but a bitter end. The star named 'Wormwood' in Revelation 8:11 continues this bitter judgment imagery.