U+21CD "⇍" Leftwards Double Arrow with Stroke Unicode Character

U+21CD "⇍" Leftwards Double Arrow with Stroke is a mathematical symbol used primarily in logic and formal notation to represent a negated or false leftward logical equivalence or biconditional, meaning it asserts that the leftward implication is not valid or does not hold between two propositions. Its design combines a leftwards double arrow, similar to the logical symbol for "if and only if," with a vertical stroke across its shaft, visually indicating negation or cancellation. This character is part of the Arrows block in Unicode and is often employed in contexts where precise logical relationships and their contradictions must be expressed without ambiguity.