If you shorten an event or the length of time that something lasts, or if it shortens, it does not last as long as it would otherwise do or as it used to do. Smoking can shorten your life When the days shorten in winter some people suffer depression. lengthen
If you shorten an object or if it shortens, it becomes smaller in length. Her father paid £1,000 for an operation to shorten her nose As they shorten, cells become more prone to disease and death. lengthen
become short or shorter; "In winter, the days shorten" make shorter than originally intended; reduce or retrench in length or duration; "He shortened his trip due to illness" make short or shorter; "shorten the skirt"; "shorten the rope by a few inches