It is meaningful in knowing how visitors interact with your site. Are they coming and then leaving without looking around? It is measured just by that metric.

It is meaningful in knowing how visitors interact with your site. Are they coming and then leaving without looking around? It is measured just by that metric. It is the percentage of people that came to your site and left without going to any other pages. Determining the root cause of a high bounce rate is a multitude of factors. In addition bounce rates can vary greatly between sites and content topics. Without knowing what your site is it is almost impossible to tell you exactly what is wrong or even if your bounce rate is out of the normal range for your site. It could be something as simple as the appearance of your site (i.e. if you are using WordPress or another CMS system where you can easily change themes, try a different theme to see if it improves any). It can even be something as simple as the color of your text that drives people away. It could also be your writing style. If it is a technical site it could be that your writing is too technical for what the reader is searching for or vice-versa. Also, if people are reaching your pages using certain keywords, but the content on the page doesn't match the keywords they will leave. This brings up another point with bounce rate too. It could be that your content is so highly focused and that when people search for and land on your pages their question is answered immediately and they have no other reason to poke around your site.