grindstone /ˈgraɪnˌstoʊn/ noun plural grindstones
plural grindstones
Learner's definition of GRINDSTONE
[count]
: a stone disc that can be turned like a wheel and that is used for sharpening tools, smoothing rough edges, etc.磨石;砂轮
nose to the grindstone
◊ If your nose is to the grindstone, you are doing hard, continuous work.连续辛勤工作