trisagion /tri-sagˈi-on/

1. An ancient hymn consisting of the words ‘O Holy God, holy and mighty, holy and immortal, have mercy on us’
2. Loosely, the Tersanctus

• petard
• petards
• petaries
• petary
• petasus
• petasuses
• petaurine
• petaurist
• petaurists
• pet aversion
• pet aversions
• petcharies
• petchary
• petcock
• petcocks
• pet-day
• pet-days
• petechia
• petechiae
• petechial
• peter
• peter-boat
• peter-boats
• petered
• petering