1to cause the death of a lot of living things [= destroy]:
Pollution is rapidly killing off plant life.
2to stop or remove something completely [= destroy]:
These figures kill off any hope that the economy is poised for recovery.
WORD CHOICE: WORD CHOICE: kill, murder, execute, put to death, kill yourself, commit suicide, slaughter, massacre, assassinateThere are many different words meaning to kill someone. Kill is the most general• He says he did not mean to kill his wife. • Thousands of soldiers were killed in the war.Use murder to talk about deliberately killing someone, especially after planning to do it• He is charged with murdering a policeman.When you are talking about killing someone as a punishment for a crime, use execute or put someone to death• He was executed by a firing squad. • the first person to be put to death in San Quentin jailIf someone deliberately causes their own death, say that they commit suicideor that someonekills himselforherself• the feeling of hopelessness that led him to commit suicide,• It was not the first time she had tried to kill herself. Slaughter and massacre mean to violently kill a large number of people who cannot defend themselves. These words are used mainly in writing or journalism• Hundreds of innocent civilians were slaughtered. • Soldiers massacred 900 men, women, and children in the village.Use assassinate to talk about killing an important person, especially a politician• J.F.Kennedy was assassinated in Dallas in 1963.
Definition from the Longman Dictionary of Contemporary English Advanced Learner's Dictionary.