1. Without problems or difficulties
   "NASA reported a trouble-free launch"

See also: untroubled

• paillasse
• pain
• pain in the ass
• pain in the neck
• pain pill
• pain sensation
• pain threshold
• pain unit
• pain-free
• Paine
• pained
• painful
• painful sensation
• painfully
• painfulness
• painkiller
• painkilling
• painless
• painlessly
• pains
• painstaking
• painstakingly
• painstakingness
• paint
• paint a picture