Word Study
oilstone
CIDE DICTIONARY
oilstone, n.
A variety of hone slate, or whetstone, used for whetting tools when lubricated with oil. [1913 Webster]
OXFORD DICTIONARY
oilstone, n. a fine-grained flat stone used with oil for sharpening flat tools, e.g. chisels, planes, etc. (cf. WHETSTONE).
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