unfamiliar

adjective

un·​fa·​mil·​iar ˌən-fə-ˈmil-yər 

: not familiar:

a

: not well-known : strange

an unfamiliar place

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

• 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

Instead, the team encountered some unfamiliar-looking fish hiding in plant roots. —Aspen Pflughoeft, Miami Herald, 7 Oct. 2025

Look for unusual sign-ins, unfamiliar devices, or changes to your personal details. —FOXNews.com, 7 Oct. 2025

Tender Buttons is a celebration of mutability, a rejoinder to rules, where words are set free from the shackles of meaning and grammatical function, made unfamiliar, and charged with power to make the world afresh. —Via Scribner, Literary Hub, 7 Oct. 2025

For those unfamiliar with Shackleton, a quick primer. —Frederick Dreier, Outside, 7 Oct. 2025

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