What is "absinthin"

Absinthin \Ab*sin"thin\, n. (Chem.) The bitter principle of wormwood ( Artemisia absinthium).
--Watts.

n. (context organic compound English) The principal compound found in wormwood (''Artemisia absinthium''), having a bitter taste: C₁₅H₂₀O₄(R:MW3 1976: page=6)

Absinthin is a naturally produced sesquiterpene lactone from the plant Artemisia absinthium ( Wormwood). It constitutes one of the most bitter chemical agents responsible for Absinthe's distinct taste. The compound shows biological activity and has shown promise as an anti-inflammatory agent, and should not to be confused with thujone, a neurotoxin also found in Artemisia absinthium.