Lockdown, Isolation, Contained

To be on lockdown, to be locked down, and we also talk about the lockdown. Indefinitely means there's no no specific end date or end time is just going to go on and on. Isolation though is basically when you are far from other people. For example, visitors to the city have been quarantined in an effort to contain the spread of the virus. To quarantine someone means to keep someone who is possibly infected separate from others. So it's similar to being confined or to be in isolation.