The name prosphora (Greek πρόσφορο) comes from the Greek word "προσφέρω" (to offer), in line with the Old Testament tradition of bread offering:
"Along with their fellowship offering of thanksgiving they are to present an offering with thick loaves of bread made with yeast" (Lev. 7:13)
A portion of the prosphora is used to prepare the antidoron (Greek αντίδωρο) during the Proskomedia, or Liturgy of Preparation. At the end of the liturgy, it is distributed instead of Holy Communion to the faithful who haven't been given one. Thus, "antidoron" means "instead of the gift": "αντί δώρο" - αντί του δώρου της Θείας Κοινωνίας (instead of the gift of Holy Communion).
