Focus on the pronunciation of killer
English definition of “killer”
/ˈkɪl·ər/ n [C]
› someone or something that causes someone or something to die: The police haven’t found the killer yet. Heart disease is a killer (= cause of death). › infml If something is described as a killer, it is very difficult: The test was a real killer. › infml A killer is also someone or something that is very entertaining or skilled: Dizzy was a killer on the trumpet.