apronym
Apronym, a portmanteau of apropos and acronym, is a word which, as an acronym or backronym, has a meaning related to the meaning of the words constituting the acronym or backronym; such as PLATO for "Programmed Logic for Automated Teaching Operations" alluding to Plato, the philosopher and teacher.
"Oral tradition indicates that the fish was the recognition symbol of the first Christians. The Greek word for it is ICHTYS, with the individual letters of the apronym for Iesòus Christòs Theòu Yiòs Sotèr (Jesus Christ the Son of God the Savior)."