Quda (渠答) is an ancient military literature word, many military books and dictionaries of past dynasties interpreted Quda (渠答) as Tiejili (铁蒺藜). Some scholars have raised objections to this, believing that Quda (渠答) and Tiejili (铁蒺藜) are not the same thing. However, the specific shape of Quda (渠答) has always been controversial. The paper argues that Qu (渠) and Da (答) are two kinds of city guard instruments, Qu (渠) is a large wooden shield, Da (答) is also written Da (荅), which is a protective curtain made with straw and bamboo. Da (答) covers the Qu (渠), so Qu (渠) and Da (答) are often associated, the words Qu (渠) and Da (答) in the literature have evolved into a polysyllabic word, which refers to the facilities of guarding the city against the enemy. Quchan (渠幨) is also written Quzhan (渠譫), Chan (幨) is a protective curtain made of cloth. Quzhan (渠幨) and Quda (渠答) are made of different materials, however, after generalization, the two meanings are close to each other.

Every meaning of the common word “Qin (親)” in Chinese has been seen in ancient times. However, its meaning of “kiss” only appeared at the end of Ming Dynasty. Scholars generally believe that this meaning is derived from extended meaning, which is worth discussing. Before the Tang Dynasty, the meaning of “kiss” was only expressed by “Wu (嗚)” and its polyphonic form. “Xin (噷)” appeared in the Song Dynasty, “Qin (唚)” and “Qin (親)” appeared in the Ming Dynasty. “Qin (親)” and “Qin (唚)” are the phonetic loan character of “Xin (噷)”. As the tail vowel [-m] final vanishes and the confluence of sharp and rounded sounds, the three sounds tend to be the same, “Xin (噷)” is a rare word, the common writing “Qin (唚)” with the change of phonetic sign and homophone substitution word “Qin (親)” appeared in the folk. “Qin (親)” has the meaning of “contact”. It is easier to establish semantic association with the meaning of “kiss” and becomes the dominant word in the concept field of “kiss”. “Xin (噷)” and “Qin (唚)” exist only in spoken dialect. “Xin (噷)” is the subsequent character of “Xin (歆)”, the “kiss” meaning of “Xin (噷)” is an extension of the “smell” meaning of “Xin (歆)”. In order to find the source of words, we should use the method of finding words based on meaning and sound, combine with dialect materials, and link up the homophone and synonymy of variant words. Only by breaking through the restriction of glyphs, can we find out the writing form containing the etymological basis of many variant words.