Zigu 字詁 "Analysis of characters" is a brief book on Chinese characters written during the early Qing period 清 (1644-1911) by Huang Sheng 黃生 (b. 1662), courtesy name Fumeng 扶孟, style Baishan 白山, from Shexian 歙縣, Anhui. He also wrote an analytical text called Yifu 義府 "Storehouse of meanings", which is often published together with the Zigu.
The name of the book is derived from that of a lost glossary of the name Gujin zigu 古今字詁 written by Zhang Ji 張揖 (early 3rd cent.), author of the Guangya 廣雅.
The glossary includes 107 (Zhou 1988) or 122 (Yao 1997) lemmata of selected characters which Huang analysed in a semantical and phonetical way, and provided corrections to errors in certain texts. In its aim, the Zigu is similar to Yan Shigu's 顏師古 (581-645) book Kuangmiu zhengsu 匡謬正俗, with the difference that Huang Sheng was more versed in the reconstruction of ancient sounds. He was thus able, for instance, to equate the names Fu Xi 伏羲 and Bao Xi 包羲 (the mythological ruler), and their many variants appearing in ancient literature, and to perceive the words zen 怎 and za 咱 as fused pronunciations of zenme 作么, and zijia 自家, respectively. The fusion of syllables had to do with the missing of the consonant-bearing "entering tone pitch" (rusheng 入聲) in northern China. He also found out that words including the component 分 commonly mean "in disorder". Yet there are also errors in Huang's text, like the wrong assumption that the word da 打 was first used during the Southern Dynasties period.