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

• casebook
• casebooks
• case-bottle
• case-bottles
• case-bound
• cased
• cased glass
• case glass
• case-harden
• case-hardened
• case-hardening
• case-hardens
• case histories
• case history
• casein
• case in one's checks
• case in point
• caseins
• case-knife
• case-knives
• case law
• case laws
• case-load
• case-loads
• casemaker