EPIGRAPH

[noun] [C] [specialized] - a saying or a part of a poem, play or book put at the beginning of a piece of writing to give the reader some idea of what the piece is aboutAt the start of 'Zen and the Art of Motorcycle Maintenance' there appears the epigraph 'And what is good, Phaedrus, And what is not good - Need we ask anyone to tell us these things?'