1. Threatening or foreshadowing evil or tragic developments
   - baleful, forbidding, menacing, minatory, ominous, sinister, threatening

See also: alarming

• nonproprietary
• nonprotractile
• nonpsychoactive
• nonpublic
• nonpurulent
• nonracial
• nonracist
• nonradioactive
• nonrandom
• nonrapid eye movement
• nonrapid eye movement sleep
• nonrational
• nonreader
• nonreciprocal
• nonreciprocating
• nonrecreational
• nonrecurring
• nonreflecting
• nonreflective
• nonreligious person
• nonremittal
• nonrenewable
• nonrepetitive
• nonrepresentational
• nonrepresentative