Bonsai: What is a double flowering or double flower species?

Tree and shrub names a whole tend to fairly conventional. That is they follow a pattern.

You know that variegated, evergreen, ornamental and more have a clear meaning. That is a slight change in the leaf colour. A year round foliage canopy. A tree that may flower but never bear fruit.

Double flower or double flowering is an interesting example.

This is a name that means the flowering species has flowers with more petals than usual.

Most flowers have a simple but common pattern. The centre of the flower with the stamen and carpel. Around this are the petals.

Double flowering species replace the stamen and carpel with more petals.

Relevant links:

Wiki: Double Flowered
https://en.wikipedia.org/wiki/Double-flowered