murderer
n. countable B1 Intermediate US //ˈmɝdɝɝ// UK //mˈɜːdəɹɐ// mur·der·er
n. a person who kills another person on purpose and against the law.
n. a person who has committed the crime of murder by intentionally and unlawfully killing another human being.
The police finally caught the murderer after a long search.
The jury spent three days deciding if the defendant was truly the murderer or just a witness.
In many classic detective novels, the murderer is often the character who appears the least suspicious during the initial investigation.
From Middle English murderere; equivalent to murder + -er.