Transubstantiation
Latin trans, "across," + substantia, "substance"
Definition
The change of the whole substance of bread and wine into the body and blood of Christ at the consecration, while the appearances remain.
The term was used by the Fourth Lateran Council (1215) and confirmed by the Council of Trent (1551). It describes what changes (the substance) and what does not (the appearances: taste, colour, weight).