Don

On Paul, for example, in Eph 6 paternes is plural, but it does not need to be, it could have been written as singular.  If singular it almost certainly would mean father, when plural it might mean either fathers or parents, as the male plural form is used for a group that contains at least 1 man all the way up to all men.

Recall the letters were read in the church meeting, most could not read. My take is the Roman spies sent to suspicious meetings were looking for confirmation that the paterfamilias was in charge, so they would hear paternes and think fathers.  But the Ephesian believers would catch it and know the OT says for kids to honor BOTH their father and mother, etc. so they would understand it as parents, perhaps with the help of an elder to explain.