The purpose of this paper is to find out how students understand and use synonymous relations. To this end, a survey was conducted and the results are as follows. According to the survey, students were learning in the order of understanding and acquiring in homonymy, synonymy, polysemy, antonymy, hypernym & hyponym. On the other hand, it was found that the degree of using of students who are familiar with synonymous relations was as follows. The reason students use the vocabulary of synonymous relations is that, first, it is to communicate well with each other. Second, it was to learn through synonyms. In fact, in learning English vocabulary, it is natural to be effective if you learn from words that are synonymous. Third is to express synonyms with a vocabulary that is not used by others, with the idea that they should look something. Fourth, it will be said that the help of learning and understanding history through synonyms is the result of proving that it is a learning method suitable for the convergence era. In the future, it will be more complicated in understanding and using the synonymous relations. However, it is clear that a situation in which more Korean, foreign languages, Chinese character, and English will be mixed will come sooner. Because the world is called a global village and is within the daily life zone, this phenomenon will accelerate.