饲

学术界对同形字的定义有争议，但学者的观点大都相似观点如下

汉字有三个面向：「形音义」，只要其中一项不同已可视为不同字，例如「生长」之「长」与「长短」之「长」读音意义皆不同，严格来说是两个字，只是写法相同，就是重形字。有时原字作他用，如「自」原为「鼻」象形，用作「自己」义后两字重形，加「畀」为声符产生分化字或后起字「鼻」。中国大陆推行汉字简化时产生了大量重形字，如「腊」之简化字「腊」与原解作小动物整体制成之肉干之「腊」重形。

此外如「发」、「发」合并为「发」，「松」、「松」合并为「松」，间接变成同形字。

In orthography and typography, a homoglyph is one of two or more graphemes, characters, or glyphs with shapes that appear identical or very similar. The designation is also applied to sequences of characters sharing these properties.

A synoglyph refers to glyphs that look different but mean the same thing. Synoglyphs are also known informally as display variants.The term homograph is sometimes used synonymously with homoglyph, but in the usual linguistic sense, homographs are words that are spelled the same but have different meanings, a property of words, not characters.