unfaithful

As an adjective unfaithful

is not having religious faith.

As a noun null is

zero, nil; the cardinal number before einn.

As a letter s

is the letter s with a.

As an adjective unfaithful is

not having religious faith.

As adjectives the difference between unfaithful and undefined

is that unfaithful is not having religious faith while undefined is lacking a definition or value.

As adjectives the difference between untrue and unfaithful

is that untrue is while unfaithful is not having religious faith.

As a noun infidelity

is unfaithfulness in marriage: practice or instance of having a sexual or romantic affair with someone other than one's spouse, without the consent of the spouse.

As an adjective unfaithful is

not having religious faith.

As adjectives the difference between unfaithful and false

is that unfaithful is not having religious faith while false is (label) one of two states of a boolean variable; logic.

As adjectives the difference between unfaithful and unloyal

is that unfaithful is not having religious faith while unloyal is not loyal.

As adjectives the difference between unfaithful and dishonest

is that unfaithful is not having religious faith while dishonest is not honest.

As adjectives the difference between unfaithful and unreliable

is that unfaithful is not having religious faith while unreliable is not reliable.

As adjectives the difference between unfair and unfaithful

is that unfair is not fair, unjust while unfaithful is not having religious faith.