Decanates

The fire signs are -
Aries
Leo
Sagittarius

Each sign is further broken down into decanates of the fire triplicity, of 10 degrees each.

For example, the sign of Aries.
00 to 09 degrees of Aries is the Aries decanate
10 to 19 degrees of Aries is the Leo decanate
20 to 29 degrees, 59 minutes and 59 seconds of Aries is the Sagittarius decanate.

So a degree of 21 Aries is in the Sagittarius decanate.

This is done with all the signs.

Some examples -

28 degrees of Cancer is the Scorpio decanate.

17 degrees of Aquarius is the Gemini decanate

Did you miss how that last one was done?

Well if you start with Aquarius, you go around to the next air sign which is Gemini. The last air sign would be Libra. Since it is 17 degrees then its the Gemini decanate.

21 degrees of Aquarius would be the Libra decanate.

What does all this mean.

It emphasizes a sign indirectly.

Like Aquarius is rising.
And the Moon is in Aquarius
And the Sun is in Aquarius
So the emphasis here is on Aquarius
This was easy to spot on a chart because it directly points to Aquarius.

But then you have this.

Venus is in the sign of Gemini at 21 degrees
So that is the 3rd decanate of the air signs which is Aquarius

Ascendant is at 25 Libra.
So that is the 2nd decanate of the air signs which is Aquarius

Moon is in Aquarius

So here we see the evidence of Aquarius coming up again indirectly and directly.

I just used the air signs but decanates are applied to all the signs.