In this paper, some terms of high school mathematics which read Chinese characters phonetically in Hangul are studied semantically. Nowadays, most terms of high school mathematics are terms of Chinese characters given the reading of them in Hangul alphabet. In such terms of Chinese characters, there are many loan-words from daily life and newly coined terms. Some such terms are examined in respect of meaningfulness and rule-ness. The degree of meaningfulness and rule-ness of loan-words from daily life are relative. Students seems familiar to loan-words usually, but it is difficult to know whether students seems to be familiar to loan-words or not. Degree of familiarity to a certain loan-word must be relative. In loan-words, there are such terms whose mathematical meaning is different from daily life meaning. Such terms are strong in rule-ness. Newly coined terms are strong in rule-ness. Students are not familiar to newly coined terms which are not used in daily life and have only mathematical meaning. In coining new terms using Chinese character, unit characters are related directly or indirectly to concept which unit characters want to express. So, It is possible to guess something unit characters want to express by investigating them. According to Vinner(1991), images can be evoked. But in case of reading Chinese characters phonetically in Hangul, it can not be guaranteed for Hangul mathematical terms to evoke images which the original mathematical terms evoked. To solve such problems semantic investigation of mathematical terms has been suggested. Through this process, transplanting images which the original mathematical terms evoked into Hangul terms are planned.