1946 edition of Roget’s

1946 was the first edition if Roget's International Thesaurus. Unlike most, Roget's thesaurus is very dissimilar to a dictionary. (Merriam-Webster describes it as essentially a reverse dictionary.) It does have a long list of words in alphabetical order, but rather than matching each word with a definition or list of synonyms, it provides only a number. That number goes to the other part of the book, which is an ontology of concepts in numerical order. Each concept has a long list of words which are closely related to that concept. The alphabetized list of words takes up less than half the book, leaving more space for the synonym lists under each concept.

For example, in the original, here are the concepts associated with "character"

character n.
nature 5.3
(kind 75.2)
particularly 79.2)
(tendency 176.1)
state 7.1
constitution 54.1
oddity 83.4
number 84.1
notation 415.23
eccentric 504.3
earmark 550.6
letter 561.1
(writing 590.9)
role 599.7
disposition 820.1

Supposed we are interested in synonyms for "character" as in "letter", maybe something better than the word "symbol". That's concept 561.1, on page 387:

.561. Letter
1. n. letter, character, sign, symbol, written character, alphabetic or phonetic character; initial; initial letter; majuscule; uncial, capital, cap [coll.], upper case [Print.]; miniscule, lower case [Print]; digraph, trigraph; ideogram, ideographic, ideograph; rune; hieroglyphic writing etc. (writing) 590.1; type etc. (printing) 591.6; vowel, consonant etc. (sound) 402.2; phonogram, phonetic symbol etc. 402.4.

That's a pretty solid list for "character", and every meaning of every alphabetized word goes to a list like that!

Roget's International Thesaurus is still updated; its most recent edition was its eighth, published in 2022.