straight grain
橸 centers on wood with a straight, even grain pattern, free from knots or irregularities.
橸 is a Japanese kokuji (国字) created from 木 (tree) and 晶 (clear, crystalline), suggesting wood with a clear, straight grain.
A tree (木) with three suns (晶) shining through it, revealing a perfectly straight, clear grain with no knots.
For まさ, imagine a master carpenter named Masa inspecting a piece of straight-grained wood: Masa -> まさ, and he nods in approval at the perfect grain.
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