現代漢語裡有兩個表示飲食義的「吃」和「喫」字，本文從文字語義切入，並著手於古漢語的語料，寫作「吃」字其實是因為「齕」（啃、咬）字的簡化，產生與表示口吃的「吃」，形成同形同音異義詞。而「喫」字則是由「齧」（啃、咬、侵蝕）字簡化而來。「吃」和「喫」的混用是基於「乞」「契」的諧音借用。

The heart of this paper is a series of etymological lessons. Modern Chinese utilizes two respective characters “吃”and “喫”to represent the meaning of eating. This research addresses the pooling of the usages of the aforementioned two characters from the perspective of semanticity and ancient Chinese corpus. Simplified from “齕”（gnaw, bite, nibble）, “吃”is homographically and homophonically identical with “齕”, but different from the latter in meaning. On the other hand, “喫” originates and is simplified from “齧”（bite, gnaw, erode）. The mutually replaceable usage between “吃”and “喫”stems from the homophonic borrowing between “乞”and “契”.