What is collective noun for governors?

There isn't a specific, widely-accepted collective noun for governors.

You could use more general terms like:

* A body of governors

* A council of governors

* A board of governors

* A group of governors

You could also use a term that reflects the specific context, like:

* A cabinet of governors (if referring to a state government)

* A committee of governors (if referring to a specific task)

Ultimately, the best collective noun depends on the specific situation and the desired tone.