What is a stellium?
Three or more planets in one sign or one house. It is where the weight of a chart sits: that style, or that area of life, is louder than everything else, and any transit through it lands on several planets at once. A person with a stellium is often described by it more than by their Sun sign.
Where astrologers disagree
Whether three counts or four, and whether the nodes and angles are included, are conventions. Here it is three planets, with the nodes left out.
In the reference library: The stellium: the definitions, a chart-wheel example, and sign vs house
Where you see this in OrbHeaven
Draw your own chart and this definition stops being abstract: the same term, with your numbers in it. Every placement, house and aspect, with the engine, the house system and the exact universal time printed underneath. No account, no email address, and nothing you type is kept.
No account, no email address, and nothing you type is kept.
The chart
What the picture is, and what the numbers on it are measuring.