quadrant

IPA/ˈkwɒdrənt/
KK[kwˈɑdrənt]IPA/ˈkwɑːdrənt/

quadrant — noun

  • quadrantsingular
  • quadrantsplural

1. Any of the four matching wedge-shaped sections produced when a full circle is sp

1.名詞B2
釋義

Any of the four matching wedge-shaped sections produced when a full circle is split by two straight lines that cross at the centre, each spanning exactly 90°.

例句

Sumin traced a quadrant of the circle using a compass for her geometry homework.

trace a quadrant + compass to draw a 90° arc

Each quadrant of the round table has a different wood pattern.

Each quadrant of [round object] + different [feature]

同義詞
  • quarter

    more general; quadrant is restricted to circular or angular contexts

  • sector

    a sector can be any fractional part of a circle; a quadrant is always one-fourth

用法筆記

A quadrant always refers to exactly one-fourth of a circle; use quarter for any other kind of fourth part.

常見錯誤

He ate a quadrant of the apple.
He ate a quarter of the apple.
💡Quadrant is a geometric shape within a circle, not just any fourth portion.

2. One of the four sections created when a space, surface, or body part is split by

2.名詞B2
釋義

One of the four sections created when a space, surface, or body part is split by two imaginary perpendicular lines, used especially in medicine to describe the abdomen and in geography to organize maps or districts.

例句

The doctor gently pressed the lower-right quadrant of Shanti's abdomen and asked if it hurt.

anatomical quadrant: lower-right quadrant of the abdomen

Hyun divided the whiteboard into four quadrants for the brainstorming session.

divide into quadrants for organizing

同義詞
  • section

    a broader term that does not imply exactly four parts

  • quarter

    general term for one of four parts; quadrant emphasises the cross-shaped dividing lines

  • zone

    a defined area, not necessarily one of four

用法筆記

Anatomical quadrants are always four — upper right, upper left, lower right, and lower left — with the navel as the centre point.

常見錯誤

The nurse checked the circular quadrant of her stomach.
The nurse checked the lower-right quadrant of her abdomen.
💡Anatomical quadrants are not circular; they are divided by vertical and horizontal lines through the navel.

3. A historical instrument with a 90° graduated arc, formerly used by sailors and a

3.名詞C1
釋義

A historical instrument with a 90° graduated arc, formerly used by sailors and astronomers to measure how far above the horizon the sun, moon, or stars appear, helping to determine latitude at sea.

例句

The sailor held the brass quadrant steady and read the sun's angle.

held + brass quadrant + read the angle

Marine archaeologists found a bronze quadrant on the sunken ship near Crete.

found a [metal] quadrant on [ship/place]

同義詞
  • sextant

    a more precise later instrument that measures 60° arcs instead of 90°

  • astrolabe

    an older, disc-shaped instrument used for similar astronomical measurements

用法筆記

Quadrants are now considered obsolete; modern navigation uses GPS and sextants. This sense appears mainly in historical or museum contexts.

常見錯誤

The captain checked the GPS with his quadrant.
The captain checked the GPS with his modern navigation device.
💡Quadrants are historical tools, not used alongside GPS.

4. Each of the four numbered regions formed on a flat coordinate grid by two straig

4.名詞B2
釋義

Each of the four numbered regions formed on a flat coordinate grid by two straight number lines, the x-axis and y-axis, crossing at a right angle; used to describe where a plotted point falls.

例句

Vivek plotted the point (-2, 5) in the second quadrant of the graph paper.

plot [coordinates] in the [ordinal] quadrant

The teacher numbered each quadrant on the coordinate grid from one to four.

quadrant on the coordinate grid

用法筆記

Quadrants are numbered counter-clockwise from the top-right section: first (+,+), second (−,+), third (−,−), fourth (+,−).

常見錯誤

A point with coordinates (-3, -5) is in the first quadrant.
A point with coordinates (-3, -5) is in the third quadrant.
💡The first quadrant contains only points where both coordinates are positive.