What is the meaning of sinister?

adjective

• Threatening or foreshadowing evil or tragic developments.
  • usage: "a baleful look"; "forbidding thunderclouds"; "his tone became menacing"; "ominous rumblings of discontent"; "sinister storm clouds"; "a sinister smile"; "his threatening behavior"; "ugly black clouds"; "the situation became ugly"
  • synonyms: baleful, forbidding, menacing, minacious, minatory, ominous, threatening
• Stemming from evil characteristics or forces; wicked or dishonorable."black deeds"; "a black lie"; "his black heart has concocted yet another black deed"; "Darth Vader of the dark side"; "a dark purpose"; "dark undercurrents of ethnic hostility"; "the scheme of some sinister intelligence bent on punishing him-Thomas Hardy
  • synonyms: black, dark
• On or starting from the wearer's left.
  • usage: "bar sinister"