Synonyms for Killer (same or very similar meaning)
WordNet sense 1 (the causal agent resulting in death):
cause of death
WordNet sense 2 (someone who causes the death of a person or animal):
slayer
WordNet sense 3 (predatory black-and-white toothed whale with large dorsal fin; common in cold seas):
grampus, orca, killer whale, Orcinus orca, sea wolf
From the ODE community, based on WordNet
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