sane 実

1　A structural element or tenon that projects out from the end of a board, post, or beam. Such projecting parts are inserted into mortises or grooves to form a joint. It can be called a tongue, i.e., a long slender projection cut from the side of a board along its full length. Then in a second member a channel is cut out of the side allowing the two members to be fitted together as a tongue and groove joint. The combination is often called sanehagi 実矧 or sanehozo 実ほぞ.
2　In the Nara and Heian periods sane referred to the underlayer of a plastered wall.