Well-formedness condition

Definition
Well-Formedness Condition (WFC) is a condition which governs the way the CV skeleton has to be associated with the melody tier. In a simplified form the WFC says that

(a) Every CV skeletal slot must be associated with at least one melody element and every melody element must be associated with at least one appropriate C or V slot. (b) Association lines must not cross.

The (b) clause of the WFC is also known as the No-Crossing Constraint.

Links

 * Utrecht Lexicon of Linguistics