untrusting

As adjectives the difference between trust and untrusting

is that trust is (obsolete) secure, safe while untrusting is without trust; not inclined to trust.

As a noun trust

is confidence in or reliance on some person or quality.

As a verb trust

is to place confidence in; to rely on, to confide, or repose faith, in.

As an adjective untrusting

is without trust; not inclined to trust.

As an adverb untrustingly is

in an untrusting manner.