sil·phi·um 
(sĭlfē-əm)
(sĭlfē-əm)n.
1. An extinct North African plant, often classified in the genus Ferula, that produced a resin that was a popular seasoning in ancient Greece and Rome. It became extinct in antiquity, probably from overharvesting and overgrazing.
2. A plant of the genus Silphium, such as the compass plant.
[Latin, from Greek silphion, perhaps of North African origin.]
- overcoat
- overcoating
- overcome
- overcommit
- overcommitment
- overcompensate
- overcompensation
- overcompensatory
- overconfidence
- overconfident
- overconfidently
- overcorrect
- overcorrection
- overcritical
- overcritically
- overcrop
- overcrowd
- overdevelop
- overdevelopment
- overdiagnose
- overdiagnosis
- overdo
- overdoer
- overdog
- overdominance