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

• balance
• coherence
• concinnity
• consonance
• consonancy
• harmony
• orchestration
• proportion
• symphony
• unity

Examples of symmetry in a Sentence

the symmetry of the human body

The building has perfect symmetry.

Recent Examples on the Web

The eyebrow trend embraces their natural growth and invites us to leave behind the obsession with symmetry. —Dulce Moncada, Glamour, 7 Apr. 2025

At a memorial service held by Vincent’s old schoolmates in California, his friends brought slices of apples to share and reminisced about the apple slices in his lunchbox, cut with absolute symmetry. —Yiyun Li, The New Yorker, 23 Mar. 2025

Meanwhile, koi competitions—where fish are judged on size, color and symmetry—are becoming major events, drawing enthusiasts from around the world. —Scott Travers, Forbes, 14 Mar. 2025

Lorentz symmetry states that the laws of physics should be the same for all observers who aren't accelerating. —Robert Lea, Space.com, 21 Feb. 2025

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