1. In actuality or reality or fact
   "in effect, they had no choice"
   - effectively

1. Exerting force or influence
   "the law is already in effect (or in force)"
   - effective, good, in force

See also: operative

• four-poster
• 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