E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
means one who has charge of the bridges. According to Varro, the highest class of the Roman priesthood had to superintend the construction of
the bridges (pontes) (See Ramsay: Roman Antiquities, p. 51.)
Well has the name of Pontifex been given
Unto the churchs head, as the chief builder
And architect of the invisible bridge
That leads from earth to heaven.
Longfellow: Golden Legend, v.
Here Longfellow follows the general notion that pontiff is from pons-facio, and refers to the tradition that a Roman priest threw over the Tiber, in the time of Numa, a sublician, or wooden bridge.
Sablicius means made of timber or piles. There were subsequently eight stone bridges, and Æmilius converted the sublician bridge into a stone one. There were fifteen pontiffs in the time of Sylla.