term for opposite/back side of a surface

I am attempting to find a term for the opposite or the back side of a
surface.

Typical terms for a:
horizontal surface are top and bottom or "on top" and underneath,
vertical surface are front and back, and for a
nautical surface are windward and leeward.

Does anyone know if there is a proper term that would describe the
opposite side of a flat surface, without regard to the surface's
orientation or whether it is horizontally or vertically situated?

Maybe primary and secondary would work but there should be a better term.

I have attempted to find the newsgroups with the highest degree of
relativity for this question, mainly knowledge in mechanical engineering
and drafting, and I apologize if this is off topic for the newsgroup.

Thank you very much for your help.

 

The usual term on mechanical drawings is "FAR SIDE". For
example, the callout for a blind hole on the opposite side
of a plate from that in a drawing view might be, "1/2-13
UNC-2B X .75 DP MIN, FAR SIDE".

Ned Simmons

 

OK, that is good. I was not aware of that one. That will prove helpful
in another area, thank you. In a mechanical drawing, the object's
orientation is predetermined and fixed. I am working to describe a base
unit with a threaded pipe that will extend down through a flat surface
like a tabletop or countertop and will be securely fastened from
underneath by a nut. For a tabletop or countertop, the term
"underneath" can be easily used, yet this same base with a threaded pipe
could be similarly attached to a wall, in which case the description
would be "fastened from the (far side) with a nut". Is there a term
that could be used to describe both situations, for a horizontal
tabletop or a vertical wall?

For further clarification, this is for a Pro Se patent application I am
working on. My background is a navy ship (submarine) mechanic with a
formal education in computer science. From your example description, I
can recall [1/2" diameter, 13 threads/inch, universal course, .75" depth
minimum].

For the independent claim, I currently have the phrase "... a
downward-extended means, possessing fastening threads and a
corresponding nut, for securely fastening said base to a surface." This
phrase will work well since a further clarification of "for securely
fastening said base from underneath the surface" may unnecessarily limit
the scope of the claim. It would be interesting to know how to properly
write this for both a horizontal and vertical surface though and this is
why I ask.

Again, thank you very much.

 

In a previous post birdpup says...

"Far Side" works equally well for both horizontal and vertical. It
means "Not on the side you are viewing"

 

Then that is exactly what I needed to know. I thank both of you very
much for your help and clarification.

 

Just thought, maybe Flipside !?

 

Obverse and reverse.

 

For a sheet of paper, the trem "verso" is often
used to denote the reverse side.

 

When dealing with cons, "Obverse" is the front, while "Reverse" is the
back.

Stretch