bilateral symmetry

American  

noun

Biology.

1. a basic body plan in which the left and right sides of the organism can be divided into approximate mirror images of each other along the midline.

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bilateral symmetry British  

noun

1. the property of an organism or part of an organism such that, if cut in only one plane, the two cut halves are mirror images of each other See also radial symmetry

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bilateral symmetry Scientific  

/ bī-lăt′ər-əl /

1. Symmetrical arrangement of an organism or part of an organism along a central axis, so that the organism or part can be divided into two equal halves. Bilateral symmetry is a characteristic of animals that are capable of moving freely through their environments.

2. Compare radial symmetry

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Etymology

Origin of bilateral symmetry

First recorded in 1850–55

Compare meaning

How does bilateral-symmetry compare to similar and commonly confused words? Explore the most common comparisons:

• radial symmetry vs. bilateral symmetry

Example Sentences

According to the new study, bilateral symmetry -- where there is only one line that divides the flower into two equal halves -- has evolved and been lost multiple times independently in sunflowers over evolutionary history.

From Science Daily

Sea anemones are from a different branch of the animal tree; they have only two layers of cells and radial rather than bilateral symmetry.

From Science Magazine

The scientists behind it say the development of bilateral symmetry was a critical step in the evolution of animal life.

From BBC

It didn’t help that they lacked bilateral symmetry, that their long stalks with blobby appendages appeared to human eyes to be distributed totally randomly.

From Nature

Another particularly lovely sequence takes advantage of the bilateral symmetry of the book.

From Los Angeles Times