Sentence:  With the great annual <WSD>cattle drives</WSD> which start from the arid plains of the Red River and the Pecos comes the wild cowboy, with his six-shooter on his hip. 
Meaning of the word marked with <WSD> tags:  The process of transporting a herd of bovine animals (such as bulls, cows, or steers) by compelling them to walk across a significant distance of countryside, under the escort of drovers on horseback and often over a period of days.