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

• 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

And, bringing a certain symmetry to her career, that’s the same message Super wants Victoria’s Secret to send to consumers. —Evan Clark, Footwear News, 14 Oct. 2025

This breaks the mirror symmetry, and the weak force is the only force to do it. —Paul Sutter, Space.com, 14 Oct. 2025

PageRank is more complicated than eigenvector centrality in part because links on the Internet are one-directional, whereas friendships in a social network are bidirectional, a symmetry that simplifies the math. —Jack Murtagh, Scientific American, 11 Oct. 2025

The new levitating rotor works because of its rotational symmetry. —Sujita Sinha, Interesting Engineering, 10 Oct. 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