pentalogy /pen-talˈə-ji/

1. A pentad, esp of published works
2. A series of five related books

• prototyping
• protoxide
• protoxides
• protoxylem
• protoxylems
• protozoa
• Protozoa
• protozoal
• protozoan
• protozoans
• protozoic
• protozoological
• protozoologies
• protozoologist
• protozoologists
• protozoology
• protozoon
• protract
• protracted
• protractedly
• protractible
• protractile
• protracting
• protraction
• protractions