Rockfall

Part of speech: noun

Definitions

1. A geological event where masses of rock collapse and descend rapidly down a slope due to gravitational forces
2. The rapid and often sudden descent of rocky materials from elevated terrain occurs, leading to potential hazards
3. A sudden downward movement of rock debris from a cliff or steep incline caused by gravity

Etymology: "Rockfall" is about as transparent as compounds get: it joins "rock" and "fall," and the sense is literal. The "rock" is the Middle English "rocke," a word of uncertain origin, while "fall" comes from Old English "feallan," which meant to drop or sink downward. Put together, the compound describes exactly what it sounds like, a mass of stone dropping from a height. The word's usefulness lies in how neatly it packages a hazard into two plain syllables. Speakers of English did not need a technical coinage to name it, since both halves were already in everyday use, and the combination reads at once as a warning sign on a mountain road or a cliff-side trail.

Synonyms: landslide, collapse, fall, landslip, debris