deviation. 1  the act of deviating. 2  departure from a standard or norm. 3  Statistics. the difference between one of a set of values and some fixed value, usually the mean of the set. 4  Navigation. the error of a magnetic compass, as that of a ship, on a given heading as a result of local magnetism. 5  Optics.
The definition of an invitation is a request for a person's attendance at an event. An example of an invitation is a printed card asking family and friends to come to the sender's wedding. 1  an inviting to come somewhere or do something. 2  the message or note used in inviting.  enticement or allurement.
First it could mean that rudeness is a growing trend in our society. Or, as I would prefer to believe, people no longer understand what the term means. Assuming the best, and that the reason guests don't RSVP to an invitation is a case of ignorance, not rudeness, I will clarify this for the record.f RSVP is written on an invitation it means the invited guest must tell the host whether or not they plan to attend the party. It does not mean to respond only if you're coming, and it does not mean respond only if you're not coming (the expression regrets only is reserved for that instance).