symmetry

noun

sym·​me·​try ˈsi-mə-trē 

plural symmetries

1

: balanced proportions

also : beauty of form arising from balanced proportions

2

: the property of being symmetrical

especially : correspondence in size, shape, and relative position of parts on opposite sides of a dividing line or median plane or about a center or axis compare bilateral symmetry, radial symmetry

3

: a rigid motion of a geometric figure that determines a one-to-one mapping onto itself

4

: the property of remaining invariant under certain changes (as of orientation in space, of the sign of the electric charge, of parity, or of the direction of time flow)

—used of physical phenomena and of equations describing them

Synonyms of symmetry

• proportion
• harmony
• balance
• orchestration
• correlation
• unity
• coherence
• equilibrium

Examples of symmetry in a Sentence

the symmetry of the human body

The building has perfect symmetry.

Recent Examples on the Web

Not only is symmetry taken into account by the arrangement of the beds, but the dark stain of the wood highlights the light stone fountain beautifully. —Ashlyn Needham, Southern Living, 16 Mar. 2026

There was a wonderful symmetry that occurred when Kate Hawley won the Oscar for best costume design for her work in Guillermo del Toro’s Frankenstein. —Laurie Brookins, HollywoodReporter, 16 Mar. 2026

This year’s Oscars, the 98th edition, will also unfold with the country at war in the Middle East, but despite that symmetry, rewatching the 2003 telecast today is to be reminded of just how radically the culture of Hollywood has been altered by the political upheavals of the early aughts. —Brent Lang, Variety, 12 Mar. 2026

Space-time itself has symmetries, for instance. —Quanta Magazine, 11 Mar. 2026

Word History

Etymology

Latin symmetria, from Greek, from symmetros symmetrical, from syn- + metron measure — more at measure

First Known Use

1563, in the meaning defined at sense 1

Phrases Containing symmetry

• bilateral symmetry
• center of symmetry
• radial symmetry

Rhymes for symmetry

• altimetry
• asymmetry
• dosimetry
• calorimetry
• colorimetry
• supersymmetry

Kids Definition

symmetry

noun

sym·​me·​try ˈsim-ə-trē 

plural symmetries

1

: balanced proportions

2

: close agreement in size, shape, and relative position of parts on opposite sides of a dividing line or plane or around a central point compare bilateral symmetry, radial symmetry

Medical Definition

symmetry

noun

sym·​me·​try ˈsim-ə-trē 

plural symmetries

1

: correspondence in size, shape, and relative position of parts on opposite sides of a dividing line or median plane or about a center or axis see bilateral symmetry, radial symmetry

2

: the property of remaining invariant under certain changes (as of orientation in space, of the sign of the electric charge, of parity, or of the direction of time flow)

—used of physical phenomena and of equations describing them