"A drop in the ocean" is a phrase that refers to something that is small and insignificant in the grand scheme of things. Synonyms for this phrase include "a drop in the bucket," "a speck in the universe," "a flea on the back of an elephant," "a grain of sand in the desert," and "a pinprick in the cosmos." All of these phrases convey the same message - that something is so small or insignificant that it is not worth focusing on. So, if you're looking for an alternative way to describe something as tiny and unimportant, try using one of these synonyms instead of "a drop in the ocean".