Excuse me-I should have type "use"

I don't think you should you the definition that "the study" gives because then the definition can be swayed by "the study". If a definition is given it should be defined by an outside source and the history of the definition should be seen how it has been used and the context in which it was used.

Independent verification-strange concept indeed

Umm...What about this?
.

"In its most common usage, the term nuclear family refers to a household consisting of a father, a mother and their children all in one household dwelling."

Just asking.