(By Jonathan Spira) Despite the fact that there are 56 million of us out there, people continue to struggle both with the definition of a knowledge worker as well as with self-identification.

If we are going to solve the problems of the knowledge economy, such as Information Overload, we need to be more comfortable with the concept of knowledge work.

In a casual setting, such as a pub, a factory worker would have no problem introducing himself saying “I’m a factory worker.” But could you picture a knowledge worker making a similar introduction, saying “Hi, I’m a knowledge worker”? (For the purposes of this discussion, we will consider the term “information worker” to have the same meaning as “knowledge worker.”)

Few of us self-identify in this fashion and even those who study the knowledge economy and knowledge workers seem to have trouble with this concept. The term “knowledge worker” itself is an overlay definition (this is a term I am creating to describe a term that one may use to further define another term, such as “economist” or “researcher”).

We can in part describe knowledge workers in terms of what they are not. They are not factory workers, they are not laborers, they are not farm or field workers (the term “out in the field” notwithstanding). But that doesn’t tell us very much. Many, but not all, knowledge workers are office workers. Some, but not all, are managers or white-collar workers. Some, but not all, are professionals, such as doctors or lawyers.

The media seems loathe to use the term. A search on the phrase “knowledge worker” in the New York Times (since 1981) produced 16 results (several relating directly to Peter Drucker, who coined the term in the 1950s). The Wall Street Journal hasn’t used the term at all in the past three months. Using Factiva.com, I found one mention in April 2007, the previous in August 2001, and four prior to 2001. (Regular readers may recall my column from exactly a year ago where a reporter from a major news and financial publication told me she didn’t think her readers would understand the term “knowledge worker”; now we know why.)

Business Week did a little better with 96, dating back to 1996. It was somewhat encouragingly that 16 were from 2007. A search on Forbes.com found only ten, and Fortune had 17 going back to 1991. The Economist looked promising, with 145 results for “knowledge worker” but when I dug deeper, that number quickly went down. When I used Google on the Economist.com Web site and got only six. (For the record, I didn’t rely on Google for these searches because it would return results that were not necessarily included in the actual publication but also in online forums).

Google does report 895,000 results for “knowledge worker” in an English-language search. When searching pages only in German, Google reports ca. 22,900 results.

One might ask, why does this even matter? I spend the majority of my time trying to understand the problems organizations are having in managing knowledge work and knowledge workers and investigating possible solutions. If the knowledge workers can’t come out of the closest, so to speak, that makes my task much more difficult.