Apsinthos (ἄψινθος) refers to wormwood (Artemisia absinthium) — an intensely bitter plant used medicinally and proverbially for bitterness and calamity. In Revelation 8:11, the name Apsinthos (Wormwood) is given to the third trumpet star that falls into the waters, making them bitter and deadly.
Wormwood in the OT (laanah) symbolizes the bitter consequences of sin and divine judgment (Jeremiah 9:15; Proverbs 5:4). In Revelation 8:10–11, the Wormwood star is the third of seven trumpet judgments — divine warning shots preceding final judgment. Bitterness is the fruit of forsaking God (Jeremiah 2:19). Yet Scripture ends not with wormwood but the river of life (Revelation 22:1–2) — pure, sweet, healing. Jesus was offered vinegar mixed with gall on the cross (Matthew 27:34), absorbing the bitterness of sin's curse so His people might drink the sweetness of eternal life.