I am defrosting a large turkey in the fridge. Once it is thoroughly cooked is it safe to freeze leftovers?

yes, once cooked it wil be fine to refreeze and save for later use. freeze soon within like a day or two tops. wrap in wax paper or put in baggie then put in a freezer bag for added protection and to prevent freezer burn. slice and put in packages that you will use at one time. say 5 slices etc. or a leg...just not all in one. so you ony are thawing a meals worth at a time.