Given external source meanings mislead readers to believe that this stone roller was used to level farmed fields. Possibly those sources are suggesting it was used for sports and recreation playing fields back in the Stone Age, since a farmed field would not need to be absolutely flat or level to be used effectively. Moreover, most farming folks do not prefer soil to be compacted by rolling heavy stones or rocks over the fields, not to mention the work that rolling a huge stone would involve. On the contrary, laborious efforts are made to do the very opposite, to loosen the soil and to keep it loose. Rice crops were planted in terraced slopes filled with muck and water, and could be leveled when needed by wading through and pushing the slurry with one's feet much more easily than by rolling a cylindrical boulder around, one that would likely sink into the muck anyway. Moreover, the weight of any rock that would be sufficiently heavy to level soil would also be a boulder too heavy to roll by most means. Rock is still today somewhat difficult to drill through when adding some sort of an axle. And needless to point out, finding a boulder shaped as is a steamroller's front end was not a very common occurrence, also very difficult to create with a hand chisel and mallet.
　Elements are「rocks for harmful prick perforating penetrations」「stone of harm, toxic, venom, poison, malicious, cruel」hence these STONE ROLLERS were more likely relatively small and wielded by the hands of shamans to roll along the soles of a young girl's feet, leveling and smashing into finer pieces any bone splinters that may have remained after the initial crunching blows. Clients did not enjoy finding a bone splinter stuck into the side or the head of a pecker, especially after paying premium prices for the services provided…in particular, see 条 and 條, and many the graphic depictions in Chinese erotic art. Men in dynastic China masturbated by wrapping no-longer-integrated feet around an erect penis ostensibly to lower the risk of contracting a sexually transmissible disease or infection that often occurred when performing coitus within some sort of mucous membrane system of a female service provider, and, to gain hand-control over the pressure applied to the foot meat surrounding a weakened penis that functioned as a living cockring.
　FOOT dis-integratING was:「…[T]he custom of applying painfully tight binding to the feet of young girls to prevent further growth. …The process was started before the arch of the foot had a chance to develop fully, usually between the ages of 2 and 5. Binding usually started during the winter months since the feet were more likely to be numb, and therefore the pain would not be as extreme. …Disease inevitably followed infection, meaning that death from septic shock could result from foot-binding, and a surviving girl was more at risk for medical problems as she grew older. …At the beginning of the binding, many of the foot bones would remain broken, often for years. However, as the girl grew older, the bones would begin to heal. Even after the foot bones had healed, they were prone to re-breaking repeatedly, especially when the girl was in her teenage years and her feet were still soft. …Bound feet were once considered intensely erotic in Chinese culture…Qing Dynasty sex manuals listed 48 different ways of playing with women's bound feet.」
　　[　https://en.wikipedia.org/wiki/Foot_binding 2012-12-17, emphasis ours　]　

Modern definitions (that generally disregard history) …excluding politically incorrect concepts and other meanings deemed offensive today; may list only pigeonholed definitions, euphemisms, or meaningless mnemonics)
Chinese: stone roller
Unihan extended: stone roller used to level fields
EDRDG: stone roller used to level fields