member of the supreme college of priests in ancient Rome, 1570s, from Latin pontifex "high priest, chief of the priests," probably from pont-, stem of pons "bridge" (see pons) + -fex, -ficis, root of facere "make" (see factitious). If so, the word originally meant "bridge-maker," or "path-maker."
Weekley points out that, "bridge-building has always been regarded as a pious work of divine inspiration." Or the term may be metaphoric of bridging the earthly world and the realm of the gods. Other suggestions trace it to Oscan-Umbrian puntis "propitiary offering," or to a lost Etruscan word, in either case altered by folk etymology to resemble the Latin for "bridge-maker." In Old English, pontifex is glossed in the Durham Ritual (Old Northumbrian dialect) as brycgwyrcende "bridge-maker."