Black moon Lilith symbol In present-day astrology, the name Lilith is usually given to a point on the horoscope that represents the direction of the actual moon's apogee, unrelated to the hypothetical second moon. When considered as a point, this Lilith is sometimes defined as the second focus of the ellipse described by the Moon's orbit; the earth is the first focus, and the apogee lies in the same direction. It takes 8 years and 10 months to complete its circuit around the zodiac.
Black Moon or Lilith is part of Astro-psychology :it is the moonspot in your radix which is most distance from the earth. It means you can not wear any mask or find ways of protection , -also subconcious levels ,you are completely 'naked' there, so most vulnerable. (How to Find All the Lilith's(= Black moon) in Your Birth Chart AstroFix)
The traditional Black Moon Lilith is the position of the mean lunar apogee as measured from the geocenter; variants of the Black Moon include replacing the mean orbit with a "true" osculating orbit or with an interpolated orbit; charting the empty focus of the Moon's orbit instead of the apogee; and measuring the desired point's barycentric or topocentric position instead of its geocentric position
Transiting Black Moon Lilith represents raw female anger and sexuality. She's currently transiting Libra, the sign of partnership, balance and social grace. This uneasy mix should stir up some interesting dynamics, since BML draws our attention to the darkness that lurks on the edges of polite ...
"Black Moon Lilith and the Tabu of Gender Dysphoria: Some Preliminary Thoughts" by Simon Wickham-Smith