脊梁
jǐ liang · HSK 7
backbone
🦴 脊梁 = 脊 spine + 梁 beam; the body's load-bearing roof-beam
脊 means spine or ridge, 梁 means a roof beam or girder. Together they name the backbone as the structural beam that holds the body upright, the way a 梁 holds up a roof.