callithumpian: a band of discordant instruments
In the early decades of the nineteenth century, callithumpian bands consisting of tin horns, bells, rattles, and other noisemakers marched through the streets on New Year's Eve, creating as much racket as possible. Callithumpians also sometimes assembled after a wedding, to serenade the happy couple outside their bedroom window. This tradition was especially common when the marriage was considered somehow questionable—a May-December match or a very recent widow for example. In Louisiana and French-speaking Canada a similar custom went by the name of charivari or, as English speakers often spelled it, shivaree. Any noisy, raucous event was apt to be referred to as a callithumpian or charivari.
The Oxford English Dictionary suggests that callithumpian may have derived from the eighteenth-century English Gallithumpians, a roisterous group who disrupted Parliamentary elections. However, as they also point out, it's just as likely to be a nonsense formation.