incredulity

As a noun incredulity

is unwillingness or inability to believe; doubt about the truth or verisimilitude of something; disbelief.

As an adjective undefined is

lacking a definition or value.

As nouns the difference between distrustfulness and incredulity

is that distrustfulness is the state or quality of being distrustful or doubtful; distrust; mistrust while incredulity is unwillingness or inability to believe; doubt about the truth or verisimilitude of something; disbelief.

As nouns the difference between scepticism and incredulity

is that scepticism is while incredulity is unwillingness or inability to believe; doubt about the truth or verisimilitude of something; disbelief.

As nouns the difference between befuddlement and incredulity

is that befuddlement is the characteristic of being befuddled while incredulity is unwillingness or inability to believe; doubt about the truth or verisimilitude of something; disbelief.

As nouns the difference between incredulity and distrust

is that incredulity is unwillingness or inability to believe; doubt about the truth or verisimilitude of something; disbelief while distrust is lack of trust or confidence.

As a verb distrust is

to put no trust in; to have no confidence in.

As nouns the difference between unbelief and incredulity

is that unbelief is an absence (or rejection) of belief, especially religious belief while incredulity is unwillingness or inability to believe; doubt about the truth or verisimilitude of something; disbelief.

As a noun incredulity is

unwillingness or inability to believe; doubt about the truth or verisimilitude of something; disbelief.

As nouns the difference between skepticism and incredulity

is that skepticism is the practice or philosophy of being a skeptic while incredulity is unwillingness or inability to believe; doubt about the truth or verisimilitude of something; disbelief.

As nouns the difference between incredulity and astonishment

is that incredulity is unwillingness or inability to believe; doubt about the truth or verisimilitude of something; disbelief while astonishment is amazement, great surprise.