If you have read the The Meaning of Liff by Douglas Adams, you will know there are lots of meanings for which there are no words. How would you sum up a nostalgic yearning which is in itself more pleasant than the thing being yearned for. Adams chose the word “Aberystwyth” based on a town name.
This is a somewhat fictional example, yet it does happen in real life as well.
Bookcrossing is the practice of leaving a book in a public place to be picked up and read by others, who then do likewise. It was recently added to the Oxford Concise Dictionary’s list of new words as were cyberwar and designer baby. Have you heard the term podcasting yet?
By failing to recognise there aren’t sufficient words, we can get trapped in trying to define everything under a single existing word or into making existing words fit. This wastes time and is a failure of communication.
So next time you find yourself in a definition war (the activity of arguing over definitions at the cost of understanding), remember it’s the understanding you want first and foremost.