unsure

As an adjective unsure

is uncertain.

As a noun speculation is

the process of thinking or meditating on a subject.

As adjectives the difference between unsure and unassured

is that unsure is uncertain while unassured is not assured.

As adjectives the difference between diffident and unsure

is that diffident is (archaic): lacking confidence in others; distrustful while unsure is uncertain.

As adjectives the difference between problematic and unsure

is that problematic is posing a problem; difficult to overcome or solve while unsure is uncertain.

As a noun problematic

is (chiefly|in the plural) a problem or difficulty in a particular field of study.

As adjectives the difference between nervous and unsure

is that nervous is (obscure) of a piece of writing: forceful, powerful while unsure is uncertain.

As adjectives the difference between unpredictable and unsure

is that unpredictable is unable to be predicted while unsure is uncertain.

As a noun unpredictable

is an unpredictable thing.

As adjectives the difference between unsure and confused

is that unsure is uncertain while confused is unable to think clearly or understand.

As a verb confused is

past tense of confuse.

As adjectives the difference between improbable and unsure

is that improbable is not likely to be true while unsure is uncertain.

As adjectives the difference between sure and unsure

is that sure is physically secure and certain, non-failing, reliable while unsure is uncertain.

As an adverb sure

is without doubt.

As an interjection sure

is yes, of course.

As adjectives the difference between adamant and unsure

is that adamant is firm; unshakeable; unyielding; determined while unsure is uncertain.

As a noun adamant

is an imaginary rock or mineral of impenetrable hardness; a name given to the diamond and other substances of extreme hardness.