interior

interior — noun

1. the inner space or area of an object, building, room, or vehicle — the parts tha

1.nounintransitiveB1
Definition

the inner space or area of an object, building, room, or vehicle — the parts that are enclosed by its outer surface or walls.

Example

The interior of the old church was decorated with beautiful paintings and gold leaf.

the interior of [building] for inner space

Karim carefully cleaned the car's interior before selling it to his neighbour.

possessive: car's interior / [something]'s interior

Common collocations
  • the interior of the house
  • car interior
  • room interior
  • building interior
  • interior space
  • interior surface
Synonyms
  • inside

    more common in everyday speech; less formal than interior

  • inner part

    emphasises the position relative to the outer surface

  • heart

    figurative use; suggests the most central or important inner area

Antonyms
  • exterior

    the outside surface or outer part of something

  • outside

    more common in everyday speech for the outer area

Grammar Patterns

the interior of [something]

Usage Note

Often contrasted with exterior (the outside). In design and architecture, interior commonly refers to the inside of a building or room.

Common Mistakes

The interior of the box was empty.
The inside of the box was empty.
For very small, everyday containers, inside sounds more natural than interior, which is more formal.

2. the inland part of a large land area that lies far from its surrounding coasts o

2.nounintransitiveB2
Definition

the inland part of a large land area that lies far from its surrounding coasts or boundaries.

Example

The Amazon's interior is home to tribes with little contact with the outside world.

the interior of [geographic region] for inland area

Tanvi and her family drove deep into the interior of Australia during their summer holiday.

deep into the interior for emphasising remoteness

Common collocations
  • interior of the country
  • interior of the continent
  • deep in the interior
  • remote interior
  • dense interior
Synonyms
  • inland

    very similar; inland is more common as an adjective or adverb

  • heartland

    emphasises cultural or economic importance of the central region

  • hinterland

    slightly more formal; can mean the rural area behind a coast or river

Antonyms
  • coast

    the land along the edge of the sea

  • border

    the official line separating two countries

Grammar Patterns

the interior of [place]

deep into the interior

in the interior

Usage Note

Distinguish from sense 1 (INSIDE PART): this sense describes a geographic region, not the inside of an object or building. It is most common when discussing large landmasses.

Common Mistakes

They explored the interior of the cave.' (when meaning a cave's inside space)
They explored the interior of Australia.
For caves, use inside or cave system; interior in geography refers to large land regions far from the coast.

3. the government ministry responsible for a country's own domestic matters, such a

3.nounintransitiveC1
Definition

the government ministry responsible for a country's own domestic matters, such as policing, elections, and public safety.

Example

France's Ministry of the Interior oversees the national police and local government services.

Ministry of the Interior — government department name

Caleb applied for a policy role at the Department of the Interior after law school.

Common collocations
  • Ministry of the Interior
  • Department of the Interior
  • interior ministry
  • Secretary of the Interior
  • interior minister
Synonyms
Antonyms
  • foreign affairs

    matters involving other countries, handled by a different ministry

  • external affairs

    another term for foreign policy and international relations

Grammar Patterns

the Interior

Ministry of the Interior

Department of the Interior

Usage Note

Used mainly in countries whose government structure includes a specific ministry with this name (e.g. France, Italy, the United States). In the US, the Department of the Interior manages natural resources and public lands, not policing.

Common Mistakes

The Interior deals with foreign trade.
The Ministry of the Interior deals with domestic law enforcement and internal security.
The Interior handles internal affairs, not international trade or foreign policy.

interior — adjective

Word family

  • interiority
    nounC2
  • interiorize
    verbC2
  • interiorization
    nounC2

Synonym discussion

Sense: noun/1

Interior (sense 1) is the most formal and precise word for the enclosed space within something, especially a building, room, or vehicle. Inside is the everyday equivalent — you would say 'the inside of a drawer' or 'go inside the house,' not 'the interior of a drawer.' Inner part emphasises position relative to the outer boundary and often pairs with physical objects: 'the inner part of a tree trunk.' Heart and core are more figurative: heart suggests the most vital or emotionally important area ('the heart of the city'), while core implies the central substance or essence ('the core of the problem'). Use interior in formal or descriptive writing about architecture, geography, or design; use inside in conversation.

inside ↗inner partheart ↗core ↗

Common collocations

Nouns

  • interior design
  • interior decorator
  • interior minister
  • interior ministry
  • interior wall
  • interior space
  • car interior
  • building interior

Adverbs

  • completely interior
  • purely interior

Phrases

  • deep into the interior
  • the interior of the country
  • Ministry of the Interior
  • Department of the Interior
  • interior and exterior

Prepositions

  • in the interior
  • into the interior
  • through the interior
  • of the interior

Etymology

LatinEnglish

Interior comes directly from Latin, where it was the comparative form of inter, meaning 'between' or 'among.' While inter means 'between,' interior literally meant 'that which is further inside' — an inner comparative, like 'more between.' It entered English in the late 15th century, first used to describe the inner part of physical objects, and later extended to geographic, governmental, and abstract senses.