Difference Between Google Organic & Google Referral Visits in Analytics
1: Google Organic Visits: Organic visits come from search engine result page. Means if a user is searching for any information on Google and goes to any site by clicking on search results page then it will be considered as Google organic visits, which is a huge source of traffic if your site is optimized perfectly.
2: Google Referral Visits: You have seen many good & informative sites have a search box for a user to do a search for information that the user is looking for. Some of these search are internal but mostly are external. Internal search will show search results from that site only, just like Wikipedia. External search is something different, its powered by any search engine like Google, Yahoo, Bing etc. Most of the external searches are powered by Google(You must have seen “Powered by Google” in many sites). The visits coming through these search result pages are considered as Google referral visits.
Next time when you are checking your analytics account keep these factors in your mind.