A more thorough explanation:

Definition: Standing by means waiting for an opportunity to respond or provide assistance. It can also refer to the silence or inaction of a person who has a duty to speak or act, especially when they possess knowledge that should be revealed.

Example: If a person sees someone drowning in a pool and they have the ability to swim and save them, but they choose to stand by and do nothing, they are guilty of standing by. They have a duty to act and their inaction could result in harm to the drowning person.

Explanation: In this example, the person who is standing by has a duty to act because they have the ability to help. Their failure to act could result in harm to the drowning person, which is why their inaction is considered a breach of duty. Standing by can also refer to situations where a person possesses knowledge that should be revealed, but they choose to remain silent. This can be harmful if the knowledge could prevent harm or injustice.