birr¹ /bûr or bir/ (esp Scot and US)

1. Impetus, force, vigour
2. A violent push (Scot)
3. Emphasis, stress in speaking
4. Any sharp whirring sound

To whirr

• jiber
• jibers
• jibes
• letter-board
• letter-boards
• letter bomb
• letter bombs
• letterbox
• letterboxed
• letterboxes
• letterboxing
• letterboxings
• letter-card
• letter-cards
• letter-carrier
• letter-carriers
• letter-clip
• letter-clips
• lettered
• letterer
• letterers
• letter-founder
• letter-founders
• letter-gae
• letterhead