a. Guiding; directing; controlling; foremost; as, a leading motive; a leading man; a leading example. -- Lead"ing*ly, adv. [1913 Webster]

Leading case (Law), a reported decision which has come to be regarded as settling the law of the question involved. Abbott. --
Leading motive [a translation of G. leitmotif] (Mus.), a guiding theme; in the musical drama of Wagner, a marked melodic phrase or short passage which always accompanies the reappearance of a certain person, situation, abstract idea, or allusion in the course of the play; a sort of musical label. Also called leitmotif or leitmotiv. --
Leading note (Mus.), the seventh note or tone in the ascending major scale; the sensible note. --
Leading question, a question so framed as to guide the person questioned in making his reply. --
Leading strings, strings by which children are supported when beginning to walk. --
To be in leading strings, to be in a state of infancy or dependence, or under the guidance of others. --
Leading wheel, a wheel situated before the driving wheels of a locomotive engine. [1913 Webster]

n. 1. The act of guiding, directing, governing, or enticing; guidance. Shak. [ 1913 Webster ]

2. Suggestion; hint; example. [ Archaic ] Bacon. [ 1913 Webster ]

pos>n.1. (Aeronautics) the front edge of an airfoil; same as Advancing edge, above. [ Webster 1913 Suppl. ]

2. the front edge of anything that moves; also used metaphorically, as the leading edge in art. See also cutting edge. [ PJC ]