Biconditional
Relationship between two propositional forms P and Q, noted as "P ↔ Q" or "P is equal to Q", which is true when P and Q both simultaneously have the same truth value and false in other cases.
Synonym for biconditional propositional form.
The biconditional truth table is:
| P | Q | P ↔ Q |
| T | T | T |
| T | F | F |
| F | T | F |
| F | F | T |