When a planet's declination is greater than the Sun's maximum declination, it is said to be Out of Bounds. The planet's energy becomes a bit unpredictable, unconventional, and may behave in a way that's exteme or outside the norm, in a positive or negative way.
Throughout the year, the Sun "moves" north and south, above and below the equator. (It looks that way from our perspective due to the tilt of the Earth's axis. This is what gives us the seasons.) There is a limit to how far north or south the Sun can "move," forming a kind of band around the middle of the Earth. That band currently extends to 23°26' north and south of the equator. The Sun reaches the farthest north or south it can go, by declination, at the solstices.
Declination measures how far north or south from Earth's equator a planet appears to be. When the planet's declination exceeds the Sun's maximum declination of 23:26 degrees, it is said to be Out of Bounds.
Most of the time, the planets orbiting the Sun, as well as the Moon, are positioned within the Sun's boundary of declination (the "bounds"). However, occasionally some of them stray farther north or south. We call this being "out of bounds" (OOB). It indicates that the planet's energy is operating at a different frequency, so to speak. It could be a bit more erratic or unpredictable. It might behave in a way that's beyond our personal control. It could reach toward some higher purpose, or at least be motivated by impulses, desires and rationale that extends beyond the conventional norms.
A good analogy for OOB is a breathtaking scene in the movie The Right Stuff when the fearless test pilot, Chuck Yeager, pushes the Lockheed Starfighter jet to its limits by flying it as high as it can go. As you can see in the dramatic video clip, there is a moment where he flies so high that he breaks out of the daylight sky into the night sky, and suddenly the stars become visible! In the same way, an OOB planet reaches for a level of energy and expression that is "out of this world" – not entirely within your control and not easily brought back to manifest in the earthly realm.
Some planets go out of bounds regularly and often, 1 to 3 times per year (Mercury, Venus, Mars). Others go OOB only rarely (Jupiter, Uranus, Pluto). And others never go out of bounds and stay within the Sun's maximum declination (Saturn, Neptune, Chiron; Saturn and Neptune used to go OOB until hundreds of years ago).
The Moon is a bit different from the other planets. Its declination changes quickly, as it zigzags north and south over the equator, through a span of about a month. How far north or south it goes varies throughout a 19-year cycle.
The Moon goes through two 9-year periods, once where it is capable of going OOB and another when it is not capable of going OOB. When it is able to go out of bounds, it does so twice per month, as the farthest zigzag peaks beyond the Sun's bounds. About half-way during its 9-year OOB phase, it reaches as high as 28:44 degrees north or south, which is called the Major Lunar Standstill. After this peak, the Moon's maximum declination gradually decreases until eventually it no longer reaches far enough to cross the Sun's bounds. The Moon remains within the Sun's bounds for another 9+ years. When the Moon's maximum declination is as low as it will go – 18:09 degrees north or south – it reaches the Minor Lunar Standstill. In this way, the Moon's maximum declination fluctuates between 18:09 and 28:44 degrees over a period of about 19 years.
When the Moon is out of bounds, our feelings and emotions may be more intense than usual, and we can be very sensitive to feeling out of place or left out, disconnected from people, and/or needing to pull back from being so closely connected to others.