lodestar
A star used as a navigation reference, particularly a pole star such as Polaris.
But to and fro at disaventure strayd; Like as a ship, whose lodestarre, suddenly Covered with cloudes, her pilot hath dismayd
Tho when her ways he could no more descry,A guiding tenet or principle.
figuratively
Selfe loue, to him ſelf tender, to the reſt tough, / Is, of iuſt iuſtice, neither roote, braunce, nor bough. / Loue (namely ſelfe loue) corruptibly growyng, / Is cheefe lodeſter of lets, in iuſtice ſhowing.
A calculated amount to award as attorney's fees derived by multiplying the reasonable number of hours spent working on a case by the reasonable hourly billing rate.
Many, though not all, of the objections to lodestars seem to us to be overstated.
Where it comes from
From Middle English lode (“journey, course”) + star, where lode is an archaic noun from the verb lithe (“to go, journey”), related to lead. Other Middle English spellings include: 14th century loode sterre, lood-sterre, lade-sterne; and 15th century lode sterre. Cognate with Old Norse leiðarstjarna, Dutch leidster, German Leitstern, Danish ledestjerne, Swedish ledstjärna.
Related words
Adapted from the Wiktionary entry lodestar (CC BY-SA 4.0).