Why are they named female and male threads?

do you practice being stupid? If you cant work that out you have problems.

The male (threaded part) SCREWS (into) the female (part), just as in real life.

Look at the part.  Is it something that is screwed INTO another thing - or is it a part getting screwed?

Better than saying it is an "inny" or an "outy"  That is so childish.

All handymen have the sacred knowledge passed down to them from Father to son.

I don't like it when people's names are limited. Shannon is gender-neutral, Chris is gender-neutral... the options are endless. If you were the fifth child in a family of five, you were simply referred to as "Number five." They only had four first names, which were identical for both genders except for the ending, which was "-us" for boys and "a" for girls.

It is not male or female thread.  It is a male or female fitting.  They now call it close or open fitting.

Sadly due to political correctness they must now all be gender neutral threads so they are all exactly the same.

Naturally this means that pipes will no longer thread into each other so duct tape sales are soaring

Are you suggesting perhaps, "part with a right hand twist fits into a receiver with a right hand twist?"��

It's just common speech.  If some people are too immature to deal with it, that's their problem.

Just wait till the progressive crowd starts to inflict it's changes in the plumbing community and we have transgender plumbing parts. 

It just makes it easy to remember and identify a part.

A part with a male thread inserts into a part with the corresponding female thread.

Is there a more appropriate or insightful way to label and differentiate such parts?

One NOT prone to confusion?

(For example: if you used "inside thread" and "outside thread"...for an "outside thread" part, do you mean that the thread is on the outside of the part, or do you mean that the part is designed to go on the outside of an inside-thread part?)