In astrology, a semi-square is a minor aspect formed when two planets or other chart factors are approximately 45 degrees apart. It is commonly associated with tension, friction, recurring pressure, and the need for adjustment between the factors involved. Its influence is usually subtler than that of a square, but it may still point to areas where discomfort or resistance encourages awareness, effort, or change. Its meaning depends on the planets or points involved, their signs and houses, the size of the orb, and how the aspect fits within the larger chart pattern.