rue

Concise Bible Dictionary:

The well-known plant, the common Ruta graveolens. It is only mentioned as a small thing which was tithed by the Pharisees (Luke 11:4242But woe unto you, Pharisees! for ye tithe mint and rue and all manner of herbs, and pass over judgment and the love of God: these ought ye to have done, and not to leave the other undone. (Luke 11:42)). It is used in the East as a condiment and as a medicine. Four species of wild rue are found in Palestine.
Ruta Graveolens

Strong’s Dictionary of Greek Words:

Greek:
πήγανον
Transliteration:
peganon
Phonic:
pay’-gan-on
Meaning:
from 4078; rue (from its thick or fleshy leaves)
KJV Usage:
rue