arch

arch — noun

1. a curved part built over an open space in a wall, bridge, or similar structure s

1.nounC2
Definition

a curved part built over an open space in a wall, bridge, or similar structure so that the sides carry what is above it

Example

Workers repaired the stone arch above the old market gate.

stone arch over an opening

A single arch carries the bridge across the narrow stream.

arch as a supporting bridge part

Common collocations
  • stone arch
  • brick arch
  • arch bridge
  • Roman arch
Synonyms
  • archway

    often means the passage or opening itself, not just the supporting curve.

  • vault

    usually refers to a larger arched roof or ceiling.

  • span

    focuses on the stretch across an opening rather than the curved form.

Antonyms
  • beam

    a straight support instead of a curved one.

  • lintel

    a straight bar above a door or window.

Grammar Patterns

a stone arch

an arch over an opening

the arch of a bridge

under a brick arch

Usage Note

Used for a part of a building or bridge that helps bear weight. Distinguish from sense 2, where the word is only about a curved appearance and may be decorative.

2. something with a rounded top like a bow, especially when it frames a space or is

2.nounC1
Definition

something with a rounded top like a bow, especially when it frames a space or is made to look attractive

Example

White balloons formed an arch at the school sports day entrance.

form an arch for decoration

The garden path ends under a rose arch beside the pond.

rose arch as an entrance frame

Common collocations
  • balloon arch
  • flower arch
  • rainbow arch
  • decorative arch
Synonyms
  • curve

    a broader word for any bent line or shape.

  • arc

    more geometric and often used for part of a circle.

  • archway

    can mean an entrance with an arch shape.

Antonyms
  • line

    a straight shape with no curve.

  • angle

    a pointed corner rather than a rounded top.

Grammar Patterns

form an arch

a flower arch

a balloon arch

an arch at the entrance

Usage Note

This sense does not require the thing to support weight. It is often used for arches made from flowers, balloons, or natural shapes such as a rainbow.

3. the raised curved area inside your foot between the heel and toes

3.nounC1
Definition

the raised curved area inside your foot between the heel and toes

Example

After the hike, the arch of Mia's foot began to ache.

the arch of the foot

These running shoes support the arch better than my old pair.

support the arch

Common collocations
  • high arch
  • fallen arches
  • arch support
  • pain in the arch
Synonyms
  • instep

    not exact; it often refers to the upper middle part of the foot.

  • foot curve

    an explanatory phrase rather than a fixed anatomical term.

Grammar Patterns

the arch of the foot

support the arch

high arches

fallen arches

Usage Note

Usually appears with words about feet, shoes, support, pain, or movement. In plural, arches often means the curved parts of both feet together.

Common Mistakes

My foot arch are weak.
My foot arches are weak.
when you talk about both feet, use the plural 'arches'.

4. a curved part in the body, such as the bend of an eyebrow or a blood vessel near

4.nounC2
Definition

a curved part in the body, such as the bend of an eyebrow or a blood vessel near the heart

Example

The makeup artist darkened the arch of Nora's eyebrow.

the arch of an eyebrow

On the scan, the doctor pointed to the arch of the main artery.

medical use: curved body structure

Common collocations
  • arch of the eyebrow
  • aortic arch
  • bony arch
  • arch of the artery
Synonyms
  • curve

    a general word; it does not sound as anatomical.

  • arc

    more formal and shape-focused than everyday body description.

Grammar Patterns

the arch of an eyebrow

the arch of an artery

a bony arch

Usage Note

Often appears in 'the arch of ...' when naming a specific body structure. Distinguish from sense 3, which is limited to the foot.

arch — verb

arch — adjective

arch — prefix

Word family

  • arched
    adjectiveC1
  • archly
    adverbC2
  • archness
    nounC2
  • archway
    nounC1

Synonym discussion

Sense: noun/1

For noun sense 1, arch is the best word when a curved part of a structure stands over an opening and helps support what is above it. Arc and curve mainly describe shape, so they do not automatically suggest a building function. Archway is close, but it often names the passage or entrance rather than the supporting form itself. Vault is more technical and usually refers to a roof or ceiling made from one or more arches. A bridge can have a stone arch, but a rainbow is better called an arc or a curve. You walk through an archway, but engineers inspect an arch.

Etymology

GreekLatinFrenchEnglish

Modern English arch brings together two historical lines. The noun and verb go back to Latin arcus, meaning a bow or curved shape, which came into English through French. The adjective and prefix meaning 'chief' or 'most important' come from Greek arkhos and arkhi-, words linked with rule and leadership. That is why arch can refer either to a curve in shape or to the highest or strongest example of something.