Act -> Actuate

Stumbled upon this in an unrelated context, that's the term I was looking for!
- [Definition](http://www.merriam-webster.com/dictionary/actuate)
- [Example](https://github.com/pyblish/pyblish-lite/blob/6bcda8a69ad21e749d2b7f7e7fbc9518e8ad2f97/pyblish_lite/control.py#L35)

"act" just doesn't cut it.
