Which term best describes jargon speech?

Jargon speech is characterized by the use of specialized terminology or phrases that are often specific to a certain field, profession, or group. This terminology may make sense to those familiar with the context but can appear nonsensical or confusing to those outside of it. When looking at the aspects of jargon speech, it often resembles adult-like communication because it employs complex terms and concepts. However, for someone not versed in the particular jargon, this speech might lack clarity and thus come off as nonsensical.

In the context of the other choices, meaningful communication refers to interactions that are clear and easily understood by all parties, which is not typically the case with jargon speech. Limited vocabulary pertains to a simplistic use of words, while pragmatic issues relate to the social aspects of communication and how effectively one uses language in context, which isn't distinctly focused on the nature of jargon itself. Thus, the term that best captures the essence of jargon speech is the description of it as adult-like speech that can become nonsensical to those unfamiliar with the terminology.