The nave is the long narrow part of a Roman basilica or a Christian church – the part where people sit in a modern church. The word “nave” comes from the Latin word for “ship”, navis, because people in the Middle Ages thought a nave looked like the bottom part of a ship turned upside-down.
Usually when people say the nave they mean the widest, center part of the church, between the main columns. The long corridors on the other side of those columns are called the aisles.
But sometimes art historians call each of those corridors a nave too, so that you’ll see books saying that Chartres Cathedral (for instance) has three naves. That just means that between the walls of the cathedral there are two rows of columns, and they divide the church into three sections.
Some big churches have five naves – a big center nave, and two aisles on either side, separated by four rows of columns.
Here is a floor plan of Chartres Cathedral, looking down at the church as if you were floating over it. You can see the two rows of columns, and the three naves (or one nave and two aisles) between the columns, and the apse at the other end.
In the Middle Ages, churches didn’t have chairs in their naves. People stood during the Mass, or they brought their own chairs.
Learn by doing: visit a church with a nave and side aisles
More about Roman basilicas
More about the parts of a church
Bibliography and further reading about Roman and medieval European architecture:
Arches to Zigzags: An Architecture ABC, by Michael J. Crosbie (2000). Shows what an arch is, or a gable, or an eave. For younger kids.
Eyewitness: Building, by Philip Wilkinson, Dave King, and Geoff Dann (2000). Lavishly illustrated, like other Eyewitness books for kids, and with good explanations of most architectural terms.
City: A Story of Roman Planning and Construction, by David Macaulay (1983).
Nave, “…the term is used to indicate that portion of a church reserved for worshippers, and including the central and side aisles, crossing transepts. The name is derived from the Latin navis, a ship, possibly with some reference to the “ship of St. Peter” or the Ark of Noah.” Catholic Encyclopedia 1913
That is to say, “the faithful are in the “bark of Peter.”
This is an additional ecclesiology for church architecture in addition to the common understanding of the “underside of a church turned upside down.”
Thanks for contributing! That’s certainly possible; Isidore of Seville doesn’t seem to know the word “nave” for a vaulted roof (he compares it to a tortoise shell instead), so the use is presumably medieval rather than ancient. The oldest use in this sense that I can find is from the 900s AD (in Spanish). Still, I’d want a reference earlier than 1913 before I believed this ‘ship of St. Peter’ or ‘ark’ idea was medieval. If you know of one, I’d be interested.