an oar pin is called thole
The middle part of an oar is called a LOOM
Macon
Oar
That's an oarlock.
An oar pin is also called a rowlock pin or a thole.
It is called feathering your oar
There are 2 parts to an oar holder. The first part is the rigger which is attached to the side of the shell. The second part is the oar lock which swivels with the stroke and keeps the oar in place. This is mounted on top of the rigger.
scull
a rowlock (UK) or an oarlock (US).
A gondola " pusher " as you put it is called a gondolier. The thing he " pushes " ( rows ) with is called an oar.
its a sweep oar