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  "body": "\n## Summary\n\nA multicategory is like a [[category|A2DE66937D]], except that a morphism has a finite list of objects as its source and one object as its target.\nSuch morphisms, called multimorphisms, compose by plugging outputs into inputs.\nMultilinear maps between vector spaces are the basic example.\nA multicategory with one object is the same as a non-symmetric operad, and every monoidal category gives a multicategory.\n\n## Explanations\n\n### L1 human\n\nMany natural maps take several inputs at once, such as the multiplication of two numbers or the dot product of two vectors.\nA category only records maps with one input, so it cannot see this directly.\nA multicategory records maps with any number of inputs and one output.\nFor example, a bilinear map $V \\times W \\to U$ is a morphism from the list $(V, W)$ to $U$.\nFeeding the outputs of two such maps into a third gives a map with four inputs.\n",
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