TeX hyphenation algorithm

9 February 2022

Wikipedia's article on hyphenation mentions the TeX typesetting system's marvellous hyphenation algorithm, and then states:

In TeX's original hyphenation patterns for American English, the exception list contains only 14 words.

A source is given, and it's TeX source code, in a file called hyphen.tex. Of course, one needs an actual computer to open a text file with such a weird extension, a phone won't do, so for the benefit of past me who was curious, here are the 14 exceptions:

They make quite a lot of sense, in my opinion, as in I can see why an algorithm would like to hyphenate present or project as pre-sent or pro-ject, or table as tab-le, or declination as de-cli-na-tion. I'm less sure about what the algorithm would've done to associate and associates, though.

On my TeXlive installation, ushyphex.tex contains around 1760 more exceptions; here's a small sample:

The file hyph-en-gb.tex from the TeX Users Group page on hyphenation patterns gives these exceptions for British English: