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

See also: untroubled

• controlling
• controlling interest
• controversial
• controversialist
• controversially
• controversy
• controvert
• controvertible
• contumacious
• contumaciously
• contumacy
• contumelious
• contumeliously
• contumely
• contuse
• contusion
• conundrum
• conurbation
• Conuropsis
• Conuropsis carolinensis
• convalesce
• convalescence
• convalescent
• Convallaria
• Convallaria majalis