This is the page every other 101 post on this blog links back to. Rather than defining a term once and hoping you remember it three articles later, we keep the full glossary here and point to it constantly.
A sample of what's inside: Sign — one of the twelve zodiac divisions of the sky. Placement — where a specific planet sits, by sign and house, at a given moment. Aspect — the angle between two planets, which determines whether they cooperate or clash. Transit — where a planet is right now, versus where it was at your birth. Synastry — comparing two people's charts directly. Composite — building one combined chart out of two people's midpoints. Orb — how much wiggle room an aspect gets before it stops counting.
We add to this list whenever a new post introduces a term that isn't here yet, so it stays the single source of truth rather than forty scattered footnotes. If a word on this blog confuses you and it isn't defined here, tell us — that's a bug, not a feature.