conceal: 1. If you conceal something, you cover it or hide it carefully , so that it cannot be seen.
2. If you conceal something such as a feeling or some info, you are careful not to let other people know about it.
hide: 1. if you hide something/yourself, you put it in a place where it cannot easily be seen or found.
2. if you hide a feeling/info, you keep it a secret so that no one knows about it.