The dealer I purchased this from (in Vermont) had it marked as a "lye board," but I am near certain it is in fact a 19th c. cheese making board, with hand-carved drain. (I've included an image of one for reference at end of photos.) I find it a supremely beautiful thing, like the most elemental drawing in the world,  and also like a painting, with the white stain from the cheese making process filling the circle and bleeding out just a bit beyond. The carved drain itself is like a moat, with one narrow path of exit at one end, widening just a bit to form a triangle at the end of the board. Art without intent indeed, but also just a gloriously essential solution to the task at hand, just what was needed and not a thing more. 

16" t x 14 15/16" w. Good condition, fantastic patina of use. A bit of splitting to the wood from age/shrinkage but sturdy and stable. I would add a wire to the back and hang it on the wall straight away.