I believe semantics are important in all aspects of life. Whether in law, medicine, science, business, information technology, or any other field; having a common language doesn't do much good if there isn't a common understanding of the words that make up the language. Since languages evolve, maintaining a common understanding of words over time is a continual challenge.
It is all too common for the familiarity of words, especially argot, to lull people into a false sense of common understanding. How many meetings have we all been to where a topic is discussed, decisions are made, and everyone walks out thinking something different in terms of what is going to happen next? Such confusion can be intentional on behalf of one or more of the parties involved in the meeting, but Hanlon's razor dictates that is the exception more than the rule. I commonly see people use the same words to mean different things when the context or participants of a discussion changes and implied qualifiers are no longer understood or known. There are times, however, when I see apathy or complacency prevent people from clarifying what is known to be misunderstood, thus willfully perpetuating confusion. It is for this reason that I have one of many worn and tattered soapboxes I must drag out of the closet from time to time.
Since I rely on geospatial sciences and information technology for part of my work, I seem to find myself frequently running into semantic overloading in discussions and documentation of related software. Some of the Tilting at Globes blog posts will discuss specific examples of where failure to address known semantic overloading makes work less productive for GIS practitioners.