# unfamiliar

/ˌənfəˈmɪɫjɝ/ (US) · /ʌnfəmˈɪliə/ (UK)

Source: https://englishreference.com/word/unfamiliar
Updated: 2026-06-20

## Senses

### 1. strange or unknown

adjective · CEFR B2

not known or recognized because you have not seen or experienced it before.

For teachers: not known or recognized; lacking the quality of being familiar through previous encounter or experience.

- The city felt scary at first because all the streets were unfamiliar to me.
- Walking through the dense fog, he found himself in an unfamiliar neighborhood where even the architecture seemed alien and unsettling.

Usage: Often followed by the preposition 'to'.

### 2. lacking knowledge

adjective · CEFR B2

not knowing much about a particular subject or how to do something.

For teachers: not having knowledge or experience of a specific subject, system, or practice.

- I am unfamiliar with this computer program, so I might need some help.
- The new manager was largely unfamiliar with the technical nuances of the project, necessitating a comprehensive briefing from the engineering team.

Usage: Usually followed by the preposition 'with'.

### 3. a stranger

noun · CEFR C2 · Literary

a person that you do not know.

For teachers: a person with whom one is not acquainted. This nominal use is significantly less common than the adjectival form.

- The dog barked loudly at the unfamiliar standing at the gate.
- In the quiet village, the arrival of an unfamiliar was always met with a mixture of curiosity and guarded silence.

Teaching tip: This noun sense is rare in modern speech; students should use 'stranger' in almost all contexts.

## Examples

- The city felt strange because the streets were unfamiliar.
- She felt nervous walking through the unfamiliar neighborhood at night without a map.
- The researcher struggled to interpret the data because the software used an unfamiliar algorithm that differed significantly from industry standards.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.