1) the situation within which something exists or happens, and that can help explain it.
2) the text or speech that comes immediately before and after a particular phrase or piece of text and helps to explain its meaning.
contest has a lot of meaning but I will give you some of them.
1) a competition to do better than other people, usually in which prizes are given.
2) an attempt, usually against difficulties, to win an election or to get power or control.