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

Supporters say the move is intended to protect workers who rely heavily on gratuities and avoid confusion for visitors unfamiliar with American tipping norms. —Peter Burke, FOXNews.com, 13 June 2026

Expect loose, watery, urgent stools, usually with cramping when consuming unfamiliar foods. —Ryan Brennan, Kansas City Star, 13 June 2026

And the scale of the challenge — hundreds of thousands of international visitors unfamiliar with North American summer heat — is genuinely unprecedented. —John Samuels, Forbes.com, 12 June 2026

Buying prescription glasses online may feel unfamiliar at first, but the process has become far more accessible in recent years. —Footwear News, 12 June 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