What does the “opposition” on the calendar mean, such as “opposition to a certain zodiac sign”?

Put the twelve zodiac signs in a circle, and the two that are opposite each other across the center of the circle are said to be in opposition, for example, the rat opposes the horse, and the rabbit opposes the chicken. For example, today is the day of Yichou, which conflicts with Xinwei. To put it simply, it is the day of Ox, which conflicts with people born in the year of Sheep. Today is not a good day for people born under the sign of Sheep. It is not appropriate to do important things, and it is best to avoid other people's work.