silphium /silˈfi-əm/

1. A plant (perh the umbelliferous Ferula tingitana) imported from Cyrenaica by the Greeks for use as a food and in medicine (historical)
2. (cap) a genus of American composites, compass plants

• hard-a-lee
• hard and fast
• hard-and-fast
• hard-and-fastness
• hard as nails
• hard at it
• hardback
• hardbacked
• hardbacks
• hardbake
• hardbakes
• hardball
• hardballs
• hardbeam
• hardbeams
• hard-billed
• hard-bitten
• hardboard
• hardboards
• hard-boiled
• hard bop
• hard card
• hard cards
• hard case
• hard cases