In other words, an hourglass shape is a (nearly) symmetric shape wide at its ends and narrow in the middle.

Saturn has an intrinsic magnetic field that has a simple, symmetric shape - a magnetic dipole.

Straight-edged symmetric shapes are used in girih.

The eye later became poorly defined while the symmetric shape of the hurricane became elongated.

Now we have to make this symmetric shape asymmetric.

The highly symmetric shapes are due to depositional growth, namely, direct deposition of water vapour onto the ice crystal.

Depending on environmental temperature and humidity, ice crystals can develop from the initial hexagonal prism into numerous symmetric shapes.

When flatfish larvae hatch they have the elongated and symmetric shape of a typical bony fish.

The coat of arms is a series of elements organised in distinct symmetric egg-like or oval shapes placed on top of one another.

Empirical studies suggest less than 0.1% of snowflakes exhibit the ideal six-fold symmetric shape.