lodestar (also loadstar)

n (a) star used as a guide in navigation, esp the pole-star 用以指示航向的星; （尤指）北极星. (b) (fig 比喻) principle that guides one's behaviour and actions （行为和行动的）指导原则.

lock-nut, lock-out, lock-stitch, lock-up, lockable, locker, locker-room, locket, lockjaw, lockout, locksmith, loco, locomotion, locomotive, locum, locus, locus classicus, locust, locution, lode, lodestone, lodge, lodgement (also lodgment), lodger, lodging, lodging-house, loess, loft, lofted, loftily, loftiness, lofty, log, log book, log cabin, log-book, log-jam, log-rolling, loganberry, logarithm,