1. Thrown in between other words or phrases; parenthetical; ejaculatory; as, an interjectional remark 
2. Pertaining to, or having the nature of, an interjection; consisting of natural and spontaneous exclamations

Encyclopedia: Interjectional

• Penstemon palmeri
• Penstemon parryi
• Penstemon rupicola
• Penstemon rydbergii
• Penstemon serrulatus
• Penstemon whippleanus
• penstock
• pent
• pent-up
• penta-
• pentacle
• pentad
• pentaerythritol
• pentagon
• Pentagon Gang
• pentagonal
• pentagram
• pentahedral
• pentahedron
• mud plantain
• mud puddle
• mud puppy
• mud stain
• mud turtle
• mud-beplastered