(1) Do I abbreviate just to save space, as Chris suggests? On coins, surely yes, in part. With repetitive formulae such as Imperial titles on official inscriptions, no doubt also. But when the most abbreviated words are written large and in ornate letters, taking up more space than full text would. This is clearly a rhetorical function, as Hugh points out. (Question: in prose inscriptions, do abbreviations cluster at the ends of long lines in the same way that ligatures and cramped letters sometimes do?)

(2) Do I abbreviate to save time or effort in writing? That’s more of an issue with modern abbreviations, I imagine. (I write ampersand rather than ai-en-dee to save time, not space.) Again large and ornate abbreviations argue against this, but it must be the case in less intricate and more cursive texts.

(3) Do I abbreviate simply because the abbreviation has come to mean more than the full word (Hugh’s “lol” example)? In English, “Dr.” means something slightly different than “doctor” (the one is a title, and the latter an occupation, and the overlap is not complete in either direction–not all Dr.s are doctors, nor are all doctors Dr.s). The abbreviation “txt”, while expanding to “t(e)xt”, has very specific reference to either an ascii format file, or a message sent by SMS. Could an abbreviation such as “DMS” or “PM” be said to have a slightly different denotation than its expansion?

(4) Do I abbreviate out of habit, because the abbreviation has become the more common form of the word? “AVGG” is just what I always write for AVGVSTI DVO, not to save space or to save time or because it has a different denotation, but just because that’s what I always write. I can’t remember the last time I typed the word “Macintosh” out in full; or “et cetera”; or “Digital Versatile Disc”.

I think this is an important discussion. I’m very interested to see more results of Tom’s abbreviations indices. As a small supplementary body of evidence in the meantime, there are two indices of abbreviations and expansions in the Inscriptions of Aphrodisias online publication.

Words that might seem important, like IMP(ERATOR) and AVG(VSTVS) are quite commonly abbreviated. I wonder whether this isn’t just a space saving device, but also a means of making the import of the inscription more accessible to a semi-literate audience. IMP would be a more easily recognized symbol than IMPERATOR, for example. A study like the one Tom mentions would be fascinating and it’s one of the reasons I look forward to the day when the majority of the inscription-based data is in a more crunchable format. I wouldn’t be surprised if some of the abbreviation, especially on monumental inscriptions, was for the purpose of broadening their impact and making the inscription more impressive.

Emoticons and abbreviations like ‘lol’ have a rhetorical purpose too (though obviously a very different one). They attempt to adjust for the lack of richness in the medium by conveying emotional state. A smiley can turn an apparently insulting comment into a joke.

Crosses and chi-rhos clearly indicate the character of an inscription, so I don’t think the comparison is off base, though again, the way they are used is quite different.

http://www.case.edu/artsci/clsc/asgle/abbrev/latin/

Now, whether the cognoscenti admit emoticons (like the one I used above) as leet-speak or not, I wonder if we’d consider that scrolls, crosses, chi-rhos and such are analogous to emoticons …

Scribes abbreviated to save space - most abbreviations tho are on coins, where one only has a limited room to glorify whoever is on the piece. Abbreviations have led to some ambiguity, though as far as I know never to such an extreme degree. Things like R could be taken as Romanus or Rex, but context usually clues on in. I made a post about Latin abbreviations some time ago on my blog here:

http://neonostalgia.com/weblog/?p=398

All the best!

Chris