1. Having or displaying all the characteristics necessary for completeness
   - full-blown 
2. Denoting a firearm of relatively large calibre

1. At top speed; with full power

See also: complete

• four-pounder
• four-pronged
• four-sided
• four-spot
• four-stroke engine
• four-stroke internal-combustion engine
• four-tailed bandage
• four-wheel
• four-wheel drive
• four-wheeled
• four-wheeler
• four-wing flying fish
• four-year-old
• fourchette
• Fourdrinier
• fourfold
• fourfold point correlation
• fourhanded
• Fourier
• Fourier analysis
• Fourier series
• fourpence
• fourpenny
• fourpenny nail
• fourscore