"SINSTER" is probably misspelled. Trying sinister instead Definition of sinister
sinister has definitions from the field of heraldry
1
[ adjective ] threatening or foreshadowing evil or tragic developments

Examples

"a baleful look" "forbidding thunderclouds" "his tone became menacing" "ominous rumblings of discontent" "sinister storm clouds" "a sinister smile" "his threatening behavior"

2
[ adjective ] stemming from evil characteristics or forces; wicked or dishonorable

Synonyms

dark black

Examples

"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"

3
[ adjective ] (heraldry) on or starting from the wearer's left

Examples

"bar sinister"

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