Tree

What's the difference between a small tree and a big bush?

Is there any difference between a bush and a hedge?

Are shrubs and bushes different?

Do rubber trees bend in high winds?

Thanks for reading.

The main difference is the number of stems. Viburnum spp can be large shrubs or small trees. Most trees have only one or a few main stems or leaders.
A hedge is clipped or unclipped but requires many plants planted near each other to achieve an effect, example: boxwood or privet. A bush is one plant like a yew bush, clipped or not. The term bush is used by lay people but almost never by landscape professionals. Ultimately there is little difference.
Rubber trees (Heavea spp) are soft wooded plants native to Brasil and would not only bend but would break in the wind. They are Euphorbes and have white milky sap. They are dioecious and need male and female plants for pollination.
Love that clotted cream.

In botany sometimes it is something over 10m's tall, sometimes even 30m before it is called a tree. Just depends no real consensus. Kind of like "vegetable". Very ambiguous.

Each discipline that deals with trees will literally have its own definition.