If you preserve a situation or condition, you make sure that it remains as it is, and does not change or end.

If you preserve something, you take action to save it or protect it from damage or decay.

Preserves are foods such as jam that are made by cooking fruit with a large amount of sugar so that they can be stored for a long time.

If you say that a job or activity is the preserve of a particular person or group of people, you mean that they are the only ones who take part in it.