unfamiliar

adjective

un·​fa·​mil·​iar ˌən-fə-ˈmil-yər 

: not familiar:

a

: not well-known : strange

an unfamiliar place

—often used with to

used words that were unfamiliar to me

b

: not well acquainted

unfamiliar with the subject

unfamiliarity

ˌən-fə-ˌmil-ˈyer-ə-tē 

-ˌmi-lē-ˈyer-, 

-ˈya-rə-

noun

unfamiliarly

ˌən-fə-ˈmil-yər-lē 

adverb

Synonyms of unfamiliar

• strange
• new
• novel
• unprecedented
• fresh
• original
• unknown

Examples of unfamiliar in a Sentence

He gets nervous when he is in unfamiliar surroundings.

The book is full of unfamiliar words.

Recent Examples on the Web

For families, this can feel like entering unfamiliar terrain. — Avni Trivedi, CNN Money, 21 July 2026

None of these ideas is unfamiliar on its own, but their combination is aimed at a clear use case—a premium folder that feels comfortable enough for everyday carry and capable enough for more serious cutting. — New Atlas, 21 July 2026

For those unfamiliar, the inspiration for this comes from Mike Sando’s NFL QB Tiers. — Antonio Morales, New York Times, 21 July 2026

Computational accuracy also does not establish the quality of instruction or show that learning transfers to unfamiliar problems. — Ray Ravaglia, Forbes.com, 21 July 2026

Word History

First Known Use

1594, in the meaning defined above

Phrases Containing unfamiliar

• unfamiliar with (something)

Rhymes for unfamiliar

• conciliar
• familiar

Kids Definition

unfamiliar

adjective

un·​fa·​mil·​iar ˌən-fə-ˈmil-yər 

1

: not well-known : strange

an unfamiliar place

2

: not well acquainted

unfamiliar with the subject

unfamiliarity

-ˌmil-ˈyar-ət-ē 

-ˌmil-ē-ˈ(y)ar-

noun