grandfather
n.— «During the purification ceremonies, anywhere from four to 20 people would pack into the tarp-covered huts. The lava rocks, or grandfathers as they are called, have already been burning for hours in the wood burner.» —“Ritual drives wedge in community” by Danielle Samaniego in Pleasant Hill Contra Costa Times (California) Aug. 15, 2005. (source: Double-Tongued Dictionary)
Further reading
David from Plymouth, Wisconsin, wonders about the expression a cord of wood. The phrase goes back to the 17th century and has to do with using a cord to measure a specific quantity of stacked wood. This is part of a complete episode.
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