Thirdeye,
We did have an Inspector require weld buildup on a vessel where they had gotten a little carried away with the grinder while replacing nozzles.  He cited the forementioned paragraph and had full support of the refinery inspection group. Repairs were made immediately. 

It will be undercut on a report until someone deems it necessary to correct me.

I agree that the forum is casual or we like to think it is. I agree that we all use slang when engaged in casual conversation.

I do find it vexing when I see nonstandard terminology used in AWS standards and specifications or in an inspection report. I finding it troublesome because the AWS documents developed by AWS committees and inspection reports written by AWS CWIs and SCWIs are suppose to be written by experts in our field. AWS codes, standards, and specifications typically include a reference to AWS A3.0, but never the less, the nonstandard term(s) appear in some of the documents. The trained CWI or SCWI should know the proper term to be used depending on the code or standard being referenced. As I stated, the inspector can keep their reports objective and will find themselves on the defensive less often when they use the proper terminology.

As for NDE reports that use a checklist of discontinuities, I agree, there is not usually a heading that lists, "a reduction in thickness", however, these are the same reports where you will find nonstandard terms such as "Lack of Fusion", "Lack of Penetration", etc. when describing the results of an examination for a structure fabricated to D1.1. Do we, as inspectors, know what is meant? I hope so, but to the person that is not as familiar with the various terms used by our industry, it can be troublesome.

Is it right or is it wrong to use nonstandard terminology? We are trying to communicate effectively and not everyone we communicate with is familiar with our terminology. If we stay with standard terms, the reader can look up the word in the industry accepted standard "AWS A3.0 Standard Welding Terms and Definitions". Consider the difficulty we have when someone from overseas writes a post in this forum. We struggle to understand their question when they don't use standard terminology or when they struggle with our language. Imagine what a difficult time they have when they read our replies and we use nonstandard terminology. Where do they go to look up a definition of a nonstandard term? Our global economy is here to stay. We need a means of communicating with our suppliers, our customers, and each other.

Let's not forget that the original question was how to interpret and evaluate a weld discontinuity that isn't described in ASME B&PV Code Section VIII using a standard AWS term. Consider the number of replies to this thread and how the problem described has been addressed. Is it undercut? We sometimes forget what "ASME" stands for, so I'll leave you with this reminder: "Alway, Sometimes, Maybe, or Except". Enough from the bully pulpit. I may have strayed from the original question raised by this thread.

Best regards - Al