"most important piece or feature," 1831, from French pièce de résistance, originally "the most substantial dish in a meal." Literally "piece of resistance;" there seems to be disagreement as to the exact signification.
"passage added to a musical composition for the purpose of bringing it to a conclusion," 1753, from Latin cauda "tail of an animal," which is of uncertain origin. De Vaan traces it to Proto-Italic *kaud-a- "part; tail," from PIE *kehu-d- "cleaved, separate," from root *khu-. He writes: "Since words for 'piece, part' are often derived from 'to cut, cleave', the tail may have been referred to as the loose 'part' of the animal."
"pertaining to or situated near a tail," 1660s, from Latin cauda "tail of an animal," which is of unknown origin, + -al (1).
bright star in the tail of the constellation Cygnus the Swan, by 1741, from Arabic Al Dhanab al Dajajah "the Hen's Tail."
"having a tail," c. 1600, from Modern Latin caudatus, from Latin cauda "tail of an animal," which is of unknown origin. Related: Caudation.