overture

[ OF. overture, F. ouverture, fr. OF. ovrir, F. ouvrir. See Overt. ] 1. An opening or aperture; a recess; a chamber. [ Obs. ] Spenser. “The cave's inmost overture.” Chapman. [ 1913 Webster ]

2. Disclosure; discovery; revelation. [ Obs. ] [ 1913 Webster ]

It was he
That made the overture of thy treasons to us. Shak. [ 1913 Webster ]

3. A proposal; an offer; a proposition formally submitted for consideration, acceptance, or rejection. “The great overture of the gospel.” Barrow. [ 1913 Webster ]

4. (Mus.) A composition, for a full orchestra, designed as an introduction to an oratorio, opera, or ballet, or as an independent piece; -- called in the latter case a concert overture. [ 1913 Webster ]