The first, fourth, seventh and tenth houses are termed angular houses. In quadrant house systems their angular house cusps are equal with the axes: the first house, the ascendant; the seventh house, the descendant; the tenth house, the Medium Coeli; and the fourth house, the Imum Coeli. In an equal house system the MC/IC axis will probably be embedded in the houses. In a whole sign house system, all four angles are normally located within houses.
Planets in angular houses are considered to be a strong influence in the horoscope, particularly so if they are close to an axis.