nounssingle-word-requests
In the image below, between the connector and the cable is a bit of stiff plastic that covers and protects the joint. The entire covering, from where the metal ends (visually) to where uniform cable begins (visually). Is there a (preferably non-technical) term for this?
Pegs which are used to locate parts together are generally called dowels:
They can be wood or metal, and can be used with glue (or slightly oversize) to actually effect a solid joint, or simply used to ensure that the parts are located correctly prior to being secured by other means.
I have furniture which is put together with wooden dowels just like the first picture and simply glued; but the cylinder head on my car engine is located with metal dowels similar to those in the second picture and then bolted to the block.
There is also the tenon which fits into a hole called a mortise. Generally these are rectangular, but could be turned and drilled respectively to provide a cylindrical fitting. The difference from a dowel is that the tenon is formed from the end of the piece it's part of.
A simple projection is called a lug:
In this photo, the two arrowed lugs have sheared, but the word describes both them (which resemble what you describe) and the long bolt-like lugs which are threaded to accept nuts.
These are often called divisions or subdivisions, whether geopolitical, geographical, or administrative.
Best Answer
There are a few different functions or features coincident with the concept you wish to terminologically identify
Each of these functions can be had independent of the other. For example, you can have a strain relief elbow which is not a terminal. You could also have a strain relief elbow which is also a termination. There frequently are straight strain relief sleeves about a foot away from the terminal end of USB cables. I guess that is where cables usually get tangled and mangled up.
You could have a termination that is not qualified for strain relief. In which case, you should not contractually tell your client that it is a strain-relieved terminal end.
In many cases, terminal ends are manually crimped as the "cable guy" requires the flexibility of non-predetermined cable lengths before cutting the cable and crimping on the termination sleeve. In such case, the wire or cable termination is usually commercially advertised as terminal sleeves. If strain relief is required, then strain-relieved terminal sleeves/boots. Where the terminal sleeve is appended with the stud appropriate to the occasion.
Reinvent the wheel
If you might seek to reinvent a term for it especially if you are involved in an entrepreneurial venture to produce such structures, you could use the term
varix. Pluralvarices, from which is derived the term for medical conditions of varicose veins or arteries. Variac might be a good brand name.Varix = a swollen section because it is identifiably different (vary) from the rest.