cross section

noun

1

a

: a cutting or piece of something cut off at right angles to an axis

also : a representation of such a cutting

b

: section sense 3b

2

: a measure of the probability of an encounter between particles such as will result in a specified effect (such as scattering or capture)

3

: a composite representation typifying the constituents of a thing in their relations

cross-section transitive verb

cross-sectional

ˈkrȯs-ˈsek-sh(ə-)nəl 

adjective

Synonyms of cross section

• sampling
• sample

Examples of cross section in a Sentence

a detailed cross section of the human brain

The drawing showed the human brain in cross section.

The class surveyed a cross section of the student body.

The people in our neighborhood are a representative cross section of American society.

Recent Examples on the Web

The men are a Chaucerian cross section—a contractor, a bureaucrat, a writer, and a doctor—brought together on a cold night in a train station’s waiting room. — James Folta, Literary Hub, 23 Sep. 2026

To construct this curve, experts formed a cross section of objects in higher dimensions, the boundary of which corresponds to the elliptic curve. — Manon Bischoff, Scientific American, 16 Sep. 2026

Primitive feathers O’Connor said some of the feathers looked highly similar to those present today in modern birds, with a central spine having a square cross section that would have helped make the feather stiff yet lightweight. — Katie Hunt, CNN Money, 15 Sep. 2026

Beyond the five-course lunch and champagne, the train activation featured a real cross section of talent, from self-development coach and influencer Nafousi to poet and model Kai-Isaiah Jamal. — Lucy Maguire, Vogue, 10 Sep. 2026

Word History

First Known Use

1835, in the meaning defined at sense 1a

Rhymes for cross section

• abjection
• advection
• affection
• bijection
• bisection
• collection
• complexion
• confection
• connection
• connexion
• convection
• correction

Kids Definition

cross section

noun

1

a

: a cutting made across something (as a log or an apple)

b

: a representation of a cross section

a cross section of a blood vessel

2

: a number of persons or things selected from a group to stand for the whole

cross-sectional

ˈkrȯs-ˈsek-sh(ə-)nəl

adjective

Medical Definition

cross section

noun

: a cutting or piece of something cut off at right angles to an axis

also : a representation of such a cutting

cross-sectional

ˌkrȯ(s)-ˈsek-shnəl, -shən-ᵊl 

adjective