1. Containing a closed ring of atoms of the same kind especially carbon atoms
   - isocyclic

See also: cyclic

• Penstemon barbatus
• Penstemon centranthifolius
• Penstemon cyananthus
• Penstemon davidsonii
• Penstemon deustus
• Penstemon dolius
• Penstemon fruticosus
• Penstemon linarioides
• Penstemon newberryi
• Penstemon palmeri
• Penstemon parryi
• Penstemon rupicola
• Penstemon rydbergii
• Penstemon serrulatus
• Penstemon whippleanus
• penstock
• pent
• pent-up
• penta-
• pentacle
• pentad
• pentaerythritol
• pentagon
• Pentagon Gang
• pentagonal