line of symmetry
nounUK /ˌlaɪn əv ˈsɪmətri/
US /ˌlaɪn əv ˈsɪmətri/
A line that cuts a shape into two matching halves.
The butterfly's wings show a line of symmetry down its middle.
OTHER MEANINGS
2. A line that divides a figure so one side is the mirror image of the other.
A square has four lines of symmetry.
3. An imaginary line about which an object or design is balanced.
The artist drew a line of symmetry through the center of the logo.
4. In math, a line where folding the shape makes both parts match exactly.
Fold the paper along its line of symmetry to check if the sides match.