Almuten
The almuten of a degree is the planet with the strongest overall claim on it — the one whose dignities at that degree add to the highest total. It is most often read for the rising degree or for the cusp of the house a question turns on.
The fuller picture
Start from the five owners of a degree: its domicile, exaltation, triplicity, term and face rulers. Give each ownership its usual weight — five, four, three, two, one — and add up what each planet holds. The winner is the almuten. It is a different question from "who rules this sign", and it frequently has a different answer, because a planet with no domicile at all can out-total the sign lord by collecting three of the smaller claims. Five degrees of Aries is the clean example: by day the almuten is the Sun, on exaltation and triplicity, ahead of Mars holding domicile and face. By night the triplicity owner changes and Mars wins it. Same degree, same table, different chart.
Which is the first thing to hold on to — the almuten is not a property of the degree. It moves with the chart's sect, because the triplicity owner does, and it moves with which of the two traditional bounds tables you work, because the term owner does. So an almuten quoted without a sect is not a finished statement, and two practitioners using different bounds tables can reach different almutens from the same rising degree without either being careless.
What it is for is a second opinion on a significator. The sign ruler of a house is the significator; the almuten of that house's cusp is the planet with the broadest claim on it, and when the two differ, that difference is the information. It says the strength attaching to the matter sits with a planet other than the obvious lord. iHorary treats that as the only interesting case: the almuten of the Ascendant is always shown, and the almuten of the house the question turns on is shown only when the rising degree's almuten is not the ruler of the rising sign — otherwise the second line has nothing to add.
Worth being clear about its standing, because the term gets quoted with more authority than we can honestly give it. In this app the almuten is a witness and not a judge: the horary judgment is run on the sign rulers, and nothing in the judgment engine reads an almuten. The one place it is promoted to a significator outright is the electional engine, where the almuten of a profile's house is taken as that house's significator with the sign ruler as the fallback. And the practice this glossary otherwise follows never uses the word — the closest thing in it is a five-option method of Bonatti's in which the planet whose bound holds a cusp degree signifies an option in its own right, which is the same promotion from score to actor by a different route.
Our own attribution for the term is inherited rather than checked. The short definition credits Ibn Ezra, and the translation problem there is real: he wrote in Hebrew, so the English wording anyone reaches is modern and in copyright even though he is not. Take the arithmetic as sound and the citation as unverified.
In your chart
The Almutens pane on the Tables stop names the almuten of the Ascendant with its score and the dignities it holds, and adds the almuten of the house your question turns on only when that first almuten is not the ruler of the rising sign. Both are computed on the chart's own sect and bounds table, so switching the terms system in Settings can change the answer. The judgment itself is run on the sign rulers, and the almuten stays a witness beside them.
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