The quality or state of being incongruous; lack of congruity; unsuitableness; inconsistency; impropriety.

Disagreement of parts; lack of symmetry or of harmony.

That which is incongruous; lack of congruity.

Congruency is the alignment of all output channels in a communication. E.g. the words, the tone of voice, the gestures are all communicating the same or similar message. Incongruency is the result of conflicting messages, eg saying "Yes, I'm sure" in a soft questioning voice ending with an upward inflection.