1. Natural and unstudied
   "lectured in a free-and-easy style"
   - casual

See also: informal

• nonradioactive
• nonrandom
• nonrapid eye movement
• nonrapid eye movement sleep
• nonrational
• nonreader
• nonreciprocal
• nonreciprocating
• nonrecreational
• nonrecurring
• nonreflecting
• nonreflective
• nonreligious person
• nonremittal
• nonrenewable
• nonrepetitive
• nonrepresentational
• nonrepresentative
• nonresident
• nonresidential
• nonresilient
• nonresinous
• nonresiny
• nonresistance
• nonresistant