Sinister/ˈsɪnɪstər/ Definition 1 of 3Pro Tip 1/3Negative Atmosphere Use 'sinister' to describe settings or events with a dark, evil vibe. The abandoned house had a sinister appearance. Pro Tip 2/3Subtle Evil It implies a subtle, sometimes understated evil or maliciousness. There was something sinister about his politeness. Pro Tip 3/3Suspense in Stories In literature or movies, 'sinister' often sets up suspense or hints at upcoming trouble. The music turned sinister, signaling danger.