In the interest of safeguarding your integrity (in your Google life and your real life), Gizmodo details how to not only clear out your browsing history but also turn off the Web History feature so Google won't be keeping a record of where you go on the internet:
While on this page, note the message, "Web History is paused." You will see an option to Resume, but stay away from that.
After that, exhale with relief that your browsing history is deleted and Google won't be cross-sharing any future browsing information with your Google accounts.
I mentioned above that if upon your initial visit to the Web History page you were greeted with the message, "Web History is Paused," you have no search history to delete so you should be okay.
One last but very important note: Gizmodo says that this still doesn't prevent Google from gathering and using your information for internal purposes, nor does it prevent Google from handing it over to law enforcement should it be requested. Nonetheless, assuming you're not a fugitive from justice, these steps will at least keep Google from inadvertently exposing your search history through your Google accounts. The last thing you want is for your innocent image search for "ultimate nudity" to end up populating your Google Accounts for all to see.