STREAMS query

[Greg Buzzard]

Can anybody provide a summary of all the *different* contexts in which
the term "stream", or "stream service", etc. is used?
I suspect that "stream", "stream service", etc.  probably fit into
that class of terms that are sufficiently overused so as to have
several (well, at least two) different context dependent meanings.

For instance, I generally consider "stream service" to imply a
protocol that (unless explicitly stated otherwise is end-to-end
reliable, i.e., guarantees delivery, eliminates duplicates, and...) 
appears as a uni-directional device interface (such as a printer,
or sensor) which cannot be backspaced or reread and for which no
explicit synchronization exists.  Is this inconsistent with the
standard Unix(?) concept of STREAM?