James M’Kay
6 min readApr 19, 2019


This is an attempt to investigate a claim which I’ve come across several times recently on social media: that, in Latin, the prefix cis- is straightforwardly the opposite of the prefix trans-, so that an English word that contains the prefix “trans-”, e.g. “trans-Atlantic”, will necessarily have an antonym substituting the prefix “cis-”. When actual Latin words are cited in this argument, they are invariably the names of two provinces Gallia Cisalpina and Gallia Transalpina, respectively: “the Celtic lands on the near side of the Alps,” what to us is part of northern Italy; and “the Celtic lands on the far side of the Alps,” roughly speaking modern France).

I shall assume we’re talking about classical Latin, and I rely on the authority of the Oxford Latin Dictionary (OLD). Digital search tools would naturally provide a much more detailed picture, but not one that would be likely to differ broadly in essentials.

Although the claim is specifically about the prefixes cis- and trans-, we start with the OLD entries for the standalone prepositions cis and trans, since the prefix form derives its meaning from the prepositional.

Trans is defined under three headings:

1. across/through;
2. on the other side of;
3. on the other side

of which 3 is an adverbial variant of 2, which yields two senses of the word trans: “across/through”, and “on the other side”.

Cis also has three headings:

1. before/within (in a temporal sense);
2. on the near side of;
3. to this side of, back across

Of these, the first corresponds to neither of the two meanings of trans (the opposite of it would be post); and the third raises intriguing possibilities but is clearly not the kind of ‘opposite of trans’ that anyone is trying to establish, since on this meaning of cis, a “cis-Atlantic” flight becomes merely the return leg of a trans-Atlantic one.

The second entry, though, does indeed look like it makes cis the opposite of of trans in its second sense. Or rather, one possible opposite: commoner by far is the alternative citra, and a comparison of the passages cited under each word in OLD suggests a further aspect: whereas no author later than the historian Livy (beginning 1st century CE) is cited for cis meaning “on this side”, citra is still being used in this sense several centuries later by the legal scholar Ulpian.

The conclusion at this stage: there is a sense in which cis is the opposite of trans, but it is never the only word used for this purpose, and becomes obsolete well before the end of the classical period.

The claim is not, however, about cis and trans, but cis- and trans-, and to these we now attend.

There are 24 words in OLD beginning cis-, but not all of these are examples of the cis- prefix. Once we have discounted a Gaulish word for a chariot, 2 Greek names for kinds of flower, 11 words derived from cista (“wicker basket”) and a few others, we are left with 4 words that display the prefix cis-: Cisalpinus, Cistiber, cismontanus, Cisrhenanus (“this side of the Rhône”), all adjectives formed by the addition of the prefix to the name of a geographical feature.

Trans- begins 106 words, of which 1 is an Etruscan word for a bird-trap, but the rest are genuine examples of the prefix. Among them are 10 adjectives formed by adding the prefix to the name of geographical features, and among those are Transalpinus, Transtiber (fun fact: there is still a neighbourhood in Rome called Trastevere, same word), transmontanus and Transrhenanus, which match our 4 cis- words perfectly.

At this point, I think it is safe to assume a regular formation of pairs of corresponding adjectives, formed from the names of geographical barriers such as mountain ranges or rivers, with the prefixes trans- and cis-, meaning “on this side of” and “on the other side of” and so indeed functioning as direct opposites to each other.

These words, however, take up a very small proportion of the listings for trans- words, the other 95 of which are verbs or verbal derivatives (such as transeo “cross over” and transitio “passage, transition”), the citations for many of which take up multiple columns of small print. To these there are no corresponding cis- words.

The conclusion seems inescapable here that the sense of trans that properly qualifies a verb, especially a verb of motion, will be the first “across/through”, to which cis is not the opposite (except in that tantalising third heading); the sense of trans that properly describes a geographical location is the second “on the far side of”, to which it is.

Two things are clear. First, cis- is only sometimes a meaningful substitute for trans-, it’s not straightforwardly the (or even an) opposite; secondly, that in all cases where it is the opposite of trans, the second element in the compound denotes a geographical barrier.

To turn to the case of the opposite of “trans-Atlantic” then, it depends on what kind of thing you are using it to describe: in the context “my trans-Atlantic friends” (“my friends on the other side of the Atlantic”), it would have the opposite “cis-Atlantic” (“my friends this side of the Atlantic”); in “trans-Atlantic flight” on the other hand, (“flight across the Atlantic”, nice verbal noun there), it wouldn’t.

Trans-/cis- is such an obscure and archaic bit of classical Latin, it’s worth considering how it comes to figure so prominently in modern discourse.

I think we can safely describe cis as a word from early Latin that survives into the classical period mainly as a prefix in the names of certain administrative territories (place names often preserve words that are long forgotten elsewhere in the language cf. Hither Green, the Netherlands, Bognor Regis); the crucial thing for its ongoing survival is that one of the infrequent occasions it features in surviving literature is in the works of Julius Caesar.

Up until the educational reforms of the 1960s (and the Cambridge Latin Course is one of the most overlooked but radical and progressive educational projects to emerge from that entire decade), pretty much everyone who went on to higher education would have been taught a bit of Latin, everyone who learned even a bit of Latin read Caesar — the military despatch style is straightforward and easy to read, the vocabulary limited, there are no women in it and plenty of violence, the story is pretty good, ideal for boys of all ages — and everyone who read Caesar would have encountered the provinces of Transalpine and Cisalpine Gaul.

Someone, therefore, who wished to impress with their knowledge of Latin, having learned only a little of it, might well imagine that cis- is pure and simple the opposite of trans- and come out with all sorts of illegitimate coinages on that basis.

A few words on the significance of all this: I don’t believe necessarily that the etymologies of words tell us much about what they ought to mean now, nor that words have occult purposes of their own: in general, I think that words don’t mean things, people mean things. Items of vocabulary are certainly not like the rings in Tolkien, that work only in the interests of the Power that forged them — which is magical thinking, if there ever was.

But there is an inherent fascination in following the traces of particular bits of language through history. And it is not completely irrelevant to contemporary debate: when people try to deploy cultural capital in an argument by, for example, asserting important-sounding knowledge, such as that of Latin, it’s always advisable to test for counterfeit.

Gallia Cisalpina in yellow