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

See also: operative

• penetratingly
• penetration
• penetration bomb
• penetrative
• penetratively
• penetrator
• Peneus
• penguin
• pengö
• penial
• penicillamine
• penicillate
• penicillin
• penicillin F
• penicillin G
• penicillin O
• penicillin V
• penicillin V potassium
• penicillin-resistant
• penicillin-resistant bacteria
• penicillinase
• penicillinase-resistant antibiotic
• Penicillium
• penile
• penile implant