Wormwood

Wormwood growing on the tomb of Father Thomas Gregory.

The term Wormwood was first mentioned by Dean Winchester in 2.13 Houses of the Holy in reference to a type of vine. Wormwood is also used as an ingredient in 4.02 Are You There, God? It's Me, Dean Winchester to stop the Witnesses.

It's wormwood. Plant associated with the dead; specifically the ones that are not at rest. I don't see it growing anywhere else, except over the murdered priest's marker. – Dean Winchester, 2.13 Houses of the Holy

Wormwood is used in Supernatural to reference a star that will come to Earth when the Apocalypse has begun. Dean figures out that the Horseman, War, arrives when this star falls to Earth

And there fell a great star from Heaven, burning like a torch. And it fell upon a river, and the the name of the star was Wormwood, and many men died. – Dean Winchester (Revelation 8:10), 5.02 Good God, Y'All

Trivia

• The name wormwood did actually appear in The Bible as a word of uncertain origin (Greek: apsinthos) which symbolizes a sort of bitterness, or figurative calamity.

See also

• The Bible
• Four Horsemen of the Apocalypse
• Spells
• War