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.
When the invitation is addressed to you âand guest,â you must decide if you want to bring someone and let the host know. If you reply only for yourself, donât show up at the wedding with a date or companion. When an invitation includes an RSVP but no response card, you can reply in writing or by email.