Drifting Along with the Tumbling Tumbleweeds

The regular gang over at Dr. Boli's has been discussing the phenomenon "Word Drift," which I learned as "Semantic Drift." They want one word for the phenomenon. My mind drifts a lot, and I was soon musing about driftwood, about how it changes shape over time and exposure to the elements, about how it becomes water-logged, then sun-bleached, then subjected to various other indignities. I then reflected on the two expressions, and I wondered if they meant different things - the one implying that the word is shifting, the other that the meaning is shifting. The thought occurred to me that "Driftword" might be a good word for the phenomen -- because of its pun on driftwood, and another pun on driftward.