unknown

/ʌnnˈə‍ʊn/

/ənˈnoʊn/

unknown

not known, identified, or familiar

antonyms : known

not known by many people; not famous

synonyms : obscure

being or having an unknown or unnamed source

synonyms : nameless

not known to exist

not known before

synonyms : strange

Unknown

an unknown and unexplored region

a variable whose values are solutions of an equation

anyone who does not belong in the environment in which they are found

synonyms : alien

Examples

1. I received a call from an unknown number.

2. She received a call from an unknown number on her telephone.

3. She received a missed call from an unknown phone number.

4. They were driven to an unknown place in the hills.