Wow. That’s a fantastic question. I’m going to give it a bump.
I keep thinking tertiary, but that means third in a list as oppossed to one third. And my google-fu is failing. I think we may need to fabricate one.
AFAIK there is only demi as reference to half of something (demi-tasse, demi-god, etc.) Semi on the other hand referw simply to a non-specific part of the whole.
In all other reference one would just use quarter, half, three-quarters, etc.
A semicircle is a half of a circle, and a hemisphere is a half of a sphere. And a hemidemisemiquaver is a half of a half of half of a quaver. So all three terms are in use meaning “half”.
By the way, “semi-” is from Latin semis, “one-half”. So since the Latin term for “one-third” is triens, I suppose you could use “triens-” or a derived form as the prefix you’re looking for.
Triens-circle. Triens-annually. Eh, it doesn’t really sing, does it?
Latin for “two-thirds”, by the way, is bes. Have fun!
That’s actually not what the word meant, and since pesky ntpickers have bugged me about it, I’m passing on the ritual. “Decimation” was a formal group punishment in which a randomly-selected tenth of the soldiers were executed.
It was meant to boost morale, apparantly.
In modern times, I (and just about everybody else) use the word to mean “clobber to a fraction, possibly one-tenth, of its former self”.
Possibly there is some technical one, but not one in common use.
For good reason – we don’t commonly divide things into thirds.
It’s much harder to do so accurately than halves. How would you produce a 1/3 circle, or 1/3 sphere? It’s not easy.
We have hemi-, demi-, semi- because it’s common to divide things in half.
Words & prefixes exist because people use them. If something doesn’t occur frequently in speech, it tends not to have a single word describing it, instead we have to use several words for it.
Maybe if things had continued to develop around the base 12 system, thirds would be a little more common. But our preferences for Base 2 and Base 10 counting puts thirds outside the system of clean cuts.
That’s true enough, but I have read that semester has nothing to do with semi, but six and therefore means 6 months (although in the US they are 15 weeks). So trimester ought to mean three months, which as it happens is also 1/3 of six months.
I am a little surprised no one has mentioned sesqui-, one and a half. For example a sesquipedalian word is one that is a foot and a half long.
In re the OP, I recall some aiuthor in a discussion about something pointing out that a great number of languages focus on dividing in half, whereas further subdivisions do not receive the same attention.
The specific point made was that in many languages, as in English, the words for “two” and “half” bear no semantic relation to one another. By the time you get to greater subdivisions, the words are similar: thee and third, four and fourth, etc. Perhaps the lack of the OP’s suffix is a related phenomenon.
Okay. What Latin prefix would imply “the fraction X such that when you multiply X by one-and-a-half, you get a half”? :dubious:
<hijack>
Could we use “sesqui-” to eliminate the use of the word “dotted” in discussing music notes? For example, a dotted quarter note is one and a half eighth notes. Using the british names,* a dotted whole note would be a sesquiminim, a dotted half note would be a sesquicrotchet, and a dotted quarter note would be a sesquiquaver or sesquaver, all of which might make decent band names.