The term basilica is of Greek origin and literally means « royal ». In Ancient Rome, the basilica was a rectangular civic building which served as tribunal, business centre and meeting place. Later, in Christian times, it came to describe a church modelled on Roman basilicas : a rectangle with a small semi-circular space at one end.
The term « basilica » can also be a title conferred on a church by the Pope - St Peter's Basilica in Rome or the church of Saint Denis in Paris being two examples.
(From Jean-Marie Guillouët, Eglises, abbayes et cathédrales, Gisserot et Mathilde Lavenu, Victorine Mataouchek, Dictionnaire d’Architecture, Gisserot.)
A collegiate church is a religious building used before the French Revolution by a college - or chapter - of canons. This should not be confused with a cathedral, a church « so called because the bishop at the head of the diocese has his seat there"¹, or an abbey church, which is a church in a monastery or abbey whose choir is reserved for the religious community, headed by an abbot.
St Martin's is a good example. It became a collegiate church in the 11th century under the impetus of an Angevin count, Foulques Nerra, and his wife Hildegarde. Having commissioned work to be carried out on the church, they installed a college of 13 canons. Like all chapters, it was dissolved during the Revolution.
(¹ From Jean-Michel Leniaud, Vingt siècles d'architecture religieuse en France).
A canon is a religious dignitary and member of a chapter who serves in a collegiate church or cathedral.
At St Martin's, the 13 canons (11 at the end of the Middle Ages) celebrated services in the church, "met weekly in the chapter house [...] to settle the affairs of the collegiate church"² and lived in the canonical quarter surrounding the building, each having access to their own personal dwelling.
(² From François Comte, Autour de la collégiale Saint-Martin : le quartier des chanoines, article du tiré-à-part 303 L'église collégiale Saint-Martin).
A sculpture or an element of architecture is said to be polychrome when it has several colours: painted or natural depending on the material.
A confessio is a small space (or room - in English: sacristy) near the choir of the church where sacred objects are stored: liturgical vessels, relics, etc.
A terracottiste is a sculptor who works with terracotta (baked clay).
« Thousands of terracotta sculptures in several hundred churches in the Sarthe, Mayenne and neighbouring départments bear witness to the activity of an original, fertile and high quality artistic centre, which developed [notably] from the middle of the 16th century until the Revolution. » (Terre et ciel. La sculpture en terre cuite du Maine, XVIe et XVIIe s. Cahiers du Patrimoine. Monum Editions du Patrimoine)