Defeasible may refer to:
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Defeasibility (linguistics), the ability of an implicature or presupposition to be cancelled
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Defeasible reasoning
In philosophical logic, defeasible reasoning is a kind of reasoning that is rationally compelling, though not deductive reasoning, deductively valid. It usually occurs when a rule is given, but there may be specific exceptions to the rule, or su ...
, a type of convincing but not demonstrative philosophical reasoning
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Defeasible logic, a non-monotonic logic to formalize defeasible reasoning
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Defeasible estate
{{Property law
A defeasible estate is created when a grantor transfers land conditionally. Upon the happening of the event or condition stated by the grantor, the transfer may be void or at least subject to annulment. (An estate not subject to such ...
, an estate created when a grantor transfers land conditionally
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