From HomoExcelsior

1. A long, narrow opening; a crack or cleft. 2. The process of splitting or separating; division. 3. A separation into subgroups or factions; a schism. 4. A normal groove or furrow, as in the liver or brain, that divides an organ into lobes or separates it into parts. 5. A break in the skin, usually where it joins a mucous membrane, producing a cracklike sore or ulcer. 6. To form a crack or cleft or cause a crack or cleft in.

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