"Coming upon" is a phrase that implies stumbling upon something unexpectedly. There are several synonyms that can replace this phrase without compromising on the intended meaning. Here are some of the frequently used synonyms for "coming upon": happening upon, chancing upon, stumbling upon, encountering, discovering, finding, uncovering, detecting, and stumbling across. All of these words indicate that a person has found or come across something without directly seeking it out. The usage of synonyms can enhance writing by adding variety and creating a more nuanced expression. Therefore, when using the phrase "coming upon" in a sentence, one can experiment with these synonyms to make the sentence more engaging.