Planetary Dignity
A classical rating of how strong or weak a planet is simply based on which zodiac sign it occupies — a planet can be "exalted" (its strongest possible sign), in its "own sign" (comfortable), "debilitated" (its weakest possible sign), or various shades in between.
A planet's dignity is one of the quickest ways to gauge how strongly it will deliver its significations — an exalted planet tends to give strong, positive results in its areas of influence, while a debilitated one may struggle unless other chart factors (like a Neechbhanga cancellation) offset it.
Each of the 9 grahas has one classically fixed exaltation sign and its exact opposite debilitation sign (e.g. the Sun is exalted in Mesha/Aries, debilitated in Tula/Libra) — shown in the Planets table as a "Dignity" verdict per planet.