Imum Coeli

Imum Coeli (abbreviated as IC) is a modern term used interchangeably to refer to either:

  • The exactly degree opposite the Midheaven; or
  • The fourth whole sign place, which is the fourth sign relative to the rising sign in a whole sign system.

Imum Coeli is a Latin term which translates roughly to “bottom of the heavens.” When referring to the point opposite the Midheaven, the IC is also called the Nadir. In many house division systems, the IC marks the fourth house cusp.

In the Hellenistic tradition, the fourth whole sign place was referred to as the subterraneous place, based on the Greek term hupogeion, meaning underground, as it was the farthest point in the natal chart below the horizon.

The Fourth House or IC is considered one of the four angular places, which are prominent locations in the natal chart, made up of the First, Fourth, Seventh, and Tenth Houses. In the modern tradition, the IC is considered one of the four major angles in the birth chart.

The IC signifies a person’s ancestral roots, home and property, foundation, and parents. As planets located near the IC are the most hidden, the IC may also represent those things that are hidden from the native, and the native’s private life.