I took a look at Urbandictionary as well as the more reliable official type sources.
Whereas I think Urbandictionary is an excellent source for figuring out slang usage, a word like glossary allows the weaknesses of a site like Urbandictionary to show.
To start with Urbandictionary doesn’t even have an entry for glossary.
But they do have an entry for gloss.
This is due to the fact that since anybody can submit an entry it just so happens that no one has done so for glossary. But because another word gloss means “shine or luster on a smooth surface” (as The New Oxford American Dictionary puts it) someone has submitted an Urbandictionary entry for that word.
In turn a second user has added the meaning of gloss that relates to glossary.
So here’s what Urbandictionary says about that gloss.
background information on something or someone; basic facts in order to get a take (probably from “glossary”, the part of a book which lists sources of information)
Oops, a few little mistakes in there.
The basic definition is okay: “background information on something or someone.”
Most of the real dictionaries I looked at would agree that a gloss is “a brief explanation.”
But then Urbandictionary says that gloss is probably from glossary and that the glossary is the part of a book listing sources of information.
Hmm. I always thought the part of the book that listed sources of information was called the bibliography.
But since I know the real answer, the statement that gloss is probably from glossary is what stood out for me.
According to the Oxford English Dictionary a glossary is a collection of glosses, so Urbandictionary got that backwards.
I guess the mistake is understandable since most people encounter glossaries at the back of books as lists of words used in the book with quick explanations of their meanings. Glossaries are also sometimes published not as the back of a book, but as a book themselves.
In this case I suppose the conventional understanding of what the difference is between an glossary and a dictionary might be that a dictionary goes into some depth in describing a word—or can do—while a glossary is strictly that quick description.
A dictionary may have several different meanings to a word; it may have sample sentences or citations in which the word was used; it may have an etymology. But a glossary keeps it simple.
That may be how we understand the difference today, but when the words first began emerging in English the distinction wasn’t quite so clear. Glossary is hundreds of years older than dictionary as a word, and the reason is, that as the OED says, a glossary is “a collection of glosses.”
Before a gloss was a quick description of something it was a quick translation of something. The first English glosses were English words written in Latin religious texts to explain what the Latin meant to the English monks who were supposed to be studying the texts. So at that point, a gloss stood alone, not in a glossary at the back of the book.
The Latin manuscript might have been penned hundreds of years earlier and then these explanatory notes added right there on the old pages either crowded between the lines or off in the margin.
Whereas the word dictionary doesn’t show up until the 1500s, gloss shows up in the 1200s.
Although we got the word from French, gloss comes from Latin and at first glossa meant “a word needing explanation.” With time that meaning changed to mean the explanation itself.
Before being a Latin word gloss was a Greek word and here’s where things get interesting.
Originally in Greek glossa was the word you used to refer to your tongue; the thing the doctor asks you to stick out when you say “ah.” The Greeks thought that foreign languages that other people spoke—their mother tongues—needed explanation, hence the transfer of meaning.
And I see that Merriam-Webster relates this old Greek word to another old Greek word glochin– or glochis meaning “a projecting point” which I guess fits with sticking out your tongue.
Five days a week Charles Hodgson produces Podictionary – the podcast for word lovers, Thursday episodes here at OUPblog. He’s also the author of Carnal Knowledge – A Navel Gazer’s Dictionary of Anatomy, Etymology, and Trivia as well as the forthcoming short format audio book Global Wording – The Fascinating Story of the Evolution of English.