button
Most of the time, avoid talking about UI elements.
When you need to discuss UI elements, use button instead of command button, option button, or action button.
When naming a button, use title case: for example,
If possible, refer to a button by its label only without using the word button. If you need to use the word button for clarity, it is lowercase. For example, references to an unnamed button such as Maximize may be clearer if you describe it as the Maximize button.