WordNet sense 1 (a soft heavy toxic malleable metallic element; bluish white when freshly cut but tarnishes readily to dull grey):

Pb

WordNet sense 2 (an actor who plays a principal role):

principal, star

WordNet sense 3 (an indication of potential opportunity):

hint, steer, tip, wind, wind, confidential information

WordNet sense 4 (a news story of major importance):

lead story

WordNet sense 5 (the introductory section of a story):

lead-in, lede

WordNet sense 6 (evidence pointing to a possible solution):

track, trail

WordNet sense 7 (the timing of ignition relative to the position of the piston in an internal-combustion engine):

spark advance

WordNet sense 8 (restraint consisting of a rope (or light chain) used to restrain an animal):

leash, tether

WordNet sense 9 (thin strip of metal used to separate lines of type in printing):

leading

WordNet sense 10 (mixture of graphite with clay in different degrees of hardness; the marking substance in a pencil):

pencil lead

WordNet sense 11 (a jumper that consists of a short piece of wire):

jumper cable, booster cable, jumper lead

WordNet sense 12 (be ahead of others; be the first):

top

WordNet sense 13 (cause something to pass or lead somewhere):

run

WordNet sense 14 (lead, extend, or afford access):

go

WordNet sense 15 (stretch out over a distance, space, time, or scope; run or extend between two points or beyond a certain point):

extend, pass

WordNet sense 16 (have as a result or residue):

leave, result

WordNet sense 17 (be conducive to):

conduce, contribute

WordNet sense 18 (be in charge of):

head

WordNet sense 19 (take somebody somewhere):

conduct, direct, guide, take, conduct

WordNet sense 20 (move ahead (of others) in time or space):

precede

WordNet sense 21 (preside over):

chair, moderate, moderate