"Normal"

An operational definition:

That which is currently and has been, in recent times (for the most recent ten year period), practiced by a majority (greater than 50%) of your population sample.

For example: working a greater-than-40-hour work week is normal while maintaining a blog of harebrained non-verbal recitations of personal literature and inner cannibalistications is not.

For example: stress, normal; congruence, saved for one or two weeks per annum.