inappropriate

Inappropriate is a related term of peculiar.

As adjectives the difference between inappropriate and peculiar

is that inappropriate is not appropriate; not suitable for the situation, time, and/or place while peculiar is out of the ordinary; odd; curious; unusual.

As a noun peculiar is

that which is peculiar; a sole or exclusive property; a prerogative; a characteristic.

As adjectives the difference between inappropriate and unconventional

is that inappropriate is not appropriate; not suitable for the situation, time, and/or place while unconventional is not adhering to convention or accepted standards.

As a noun unconventional is

something or someone that is unconventional.

As adjectives the difference between inappropriate and inadmissible

is that inappropriate is not appropriate; not suitable for the situation, time, and/or place while inadmissible is not admissible, especially that cannot be admitted as evidence at a trial.

Uncharacteristic is a related term of inappropriate.

As adjectives the difference between uncharacteristic and inappropriate

is that uncharacteristic is not characteristic while inappropriate is not appropriate; not suitable for the situation, time, and/or place.

Inappropriate is a synonym of offensive.

As adjectives the difference between offensive and inappropriate

is that offensive is causing offense; arousing a visceral reaction of disgust, anger, or hatred while inappropriate is not appropriate; not suitable for the situation, time, and/or place.

As a noun offensive

is an attack.

As adjectives the difference between unsubstantiated and inappropriate

is that unsubstantiated is lacking substantiation; without evidence while inappropriate is not appropriate; not suitable for the situation, time, and/or place.

As adjectives the difference between inappropriate and unsuited

is that inappropriate is not appropriate; not suitable for the situation, time, and/or place while unsuited is not suited to a specific purpose.