1. An issue whose settlement is more important than anything else; and issue that must be settled before anything else can be settled

Type of: issue

• periodic sentence
• periodic table
• periodical
• periodical cicada
• periodically
• periodicity
• periodontal
• periodontal disease
• periodontia
• periodontic
• periodontics
• periodontist
• periodontitis
• perioperative
• Periophthalmus
• periosteum
• peripatetic
• peripateticism
• Peripatidae
• Peripatopsidae
• Peripatopsis
• peripatus
• peripeteia
• peripetia
• peripety