killer >> ˈkɪlə
Definition: [noun] a person or thing that kills.
Example: there's a killer on the loose
Definition: [noun] an extremely difficult or unpleasant thing.
Example: the shift system was a killer
Definition: [noun] an animal that has been selected for slaughter.
Definition: [adjective] denoting a person or thing that kills.
Example: a killer virus
Definition: [adjective] extremely difficult or unpleasant.
Example: I woke up with a killer hangover