responsibility
/rɪˌspɑːnsəˈbɪləti/
noun
plural -ties
[noncount] :the state of being the person who caused something to happen
a duty or task that you are required or expected to do [count]
[count] :something that you should do because it is morally right, legally required, etc.
[noncount] :the state of having the job or duty of dealing with and taking care of something or someone
[noncount] :the quality of a person who can be trusted to do what is expected, required, etc.
on your own responsibility
To do something on your own responsibility is to do it without being told to and to accept the blame if it has a bad result.