I couldn't resist a piano recital with that title, performed by the ubiquitous Sarah Cahill (who's gotten a lot more ubiquitous in my concert-going since I got on her publicist's mailing list, which is how I found out about this), and held as it was at a local arts school, so it was easy for me to get to. A chaconne is a work with a 4- or 8-bar sequence of notes or chords that repeats continually and forms the harmonic foundation rather than a melodic seed, though it may move from voice to voice or be fragmented or hidden.
The title was a little exaggerated, as the 6 works included nothing from the 19th century, but there were 17th and 18th century Baroque keyboard works by Purcell, Handel, and Élisabeth Jacquet de La Guerre. From the 20th and 21st centuries, we had works inspired by Handel or Bach, as a modern usage of the term chaconne implies. The composers were Nielsen (a rather jaunty piece), Gubaidulina (very modernist, except for a section imitating a Bach fugue), and a composer not only living but present in the audience, Danny Clay, whose Still Cycles takes chords and trills from the Handel piece we'd heard earlier and repeats them between long pauses, creating a quiet and hypnotic music that sounds more like Morton Feldman than anything else.
It was Clay, invited to help explain what a chaconne is, who suggested that what the repeating harmonic sequence does could be called "looping."
To a post-concert audience question from a little girl about what age she started playing the piano (6), Cahill also said that her preferred practice mode is simply to sit at the piano all day. Recently, she said, she was in D.C. at the National Gallery and got to practice at their piano all day, after which they told her that this was the instrument that had accompanied Marian Anderson at her 1939 Lincoln Memorial concert. How cool is that?