What does the word acrostic mean?

Usage examples for acrostic

  1. As both Allison and Kitty had real talent for drawing, the girls who saw the pages they decorated were moved to envy; and when Betty added an acrostic on the name Magnolia, nobody had a word of ridicule for the little Album of the Heart, that was serving two generations as a storehouse of sentiment. – The Little Colonel at Boarding-School by Annie Fellows Johnston
  2. The crew are guessing at an acrostic, and occasionally they get a glimmering of it. – Literary Lapses by Stephen Leacock