Boyd’s Bible Dictionary:
(thick-leaved). A shrubby, medicinal plant, cultivated in the gardens of the east. Tithable (Luke 11:42).
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 11:42). 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:
Meaning:
from 4078; rue (from its thick or fleshy leaves)