Swing open is a common phrase that describes the motion of a door or gate opening on hinges. However, there are a variety of synonyms that can be used to describe this action. For example, a door can be said to "fling open" if it opens suddenly and forcefully. If a door opens smoothly and effortlessly, it can be described as "gliding open." Alternatively, a door or gate that opens partially can be described as "creaking open" or "cracking open." Lastly, a door that opens outward can be referred to as "swinging out." As with any language, using a variety of synonyms not only adds nuance to your writing or speech, but it expands your vocabulary to communicate more effectively.