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  "body": "\n## Summary\n\nJónsson terms are a finite chain of ternary terms of a [[variety|AJNZJD8442]] that connect the first projection to the third by identities.\nBy Jónsson's theorem, a variety has Jónsson terms if and only if it is a [[congruence-distributive variety|9GZ7F6ETC6]].\nThey give a Mal'cev condition for congruence distributivity, so this property of all algebras of a variety reduces to the existence of finitely many terms.\n\n## Explanations\n\n### L1 human\n\nJónsson terms are a list of formulas with three inputs that step from the formula $x$ to the formula $z$.\nEach formula returns $x$ when the first and the last input agree.\nNeighbouring formulas agree when two particular inputs are equal.\nFor lattices, one middle step suffices: the majority formula, which returns the value that appears at least twice.\n",
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