To kill is to end the life of some living being or something else. So, you could kill a deer by shooting it with a hunting rifle or kill a bill by voting against it.
Hunters kill animals for their meat, and drivers sometimes kill an animal accidentally, or inadvertently kill a plant, simply by forgetting to water it. Certain inanimate things are also said to kill, like poison or disease or drunk driving. In each of these cases, death is caused and life is taken. You can also kill figuratively, as when a school board kills the foreign language program or a thunderstorm kills your hopes of a picnic.