Both minute and second owe their existence as words to one famous book from Classical Antiquity. Yet their etymologies are a surprising mix, with not only Greek and Latin but also Arabic ingredients. How come?
Let’s start with the book: it’s called the Almagest and was written in the second century CE by the mathematician and astronomer Claudius Ptolemy, a Greek in Roman Egypt. In it, he did what scholars had been doing for ages: divide the circle into 360 degrees, each degree into sixty minutes and each minute into sixty seconds.* But ‘minute’ and ‘second’ were not the words he used, for they did not yet exist. What he wrote was ‘first sixtieth’ (prota heksēkosta) and ‘second sixtieth’ (deutera heksēkosta), which in a freer translation might come out as ‘one sixtieth of the first order’ and ‘one sixtieth of the second order’.
In the year 827, the Almagest was translated into Arabic, and then in 1175 the result was translated again, now into Latin. It is in this Latin version that somewhat familiar words pop up for the first time, namely pars minuta (or sometimes pars minuta prima), that is the ‘(first) small part’, and pars minuta secunda, the ‘second small part’. (If you prefer to translate minuta as ‘minute’, pronounced as ‘my newt’, go ahead.) As you can see, any concept of ‘sixtieth’ had got lost in translation. And for reasons of efficiency, the two terms were commonly abbreviated to minuta and secunda – I mean, it’s practically impossible to even say ‘pars minuta secunda’ within a pars minuta secunda.
Provisional conclusion: our words minute (the one rhyming with in it) and second come from Latin, and the Latin words were inspired by the Greek – they were calques or loan translations, as linguists call this particular type of borrowing. So why did I mention Arabic influence at all? Well, the Arabic words for these two units of time are (and seem to have been for many centuries) daqīqa, which is literally ‘something small’, for ‘minute’, and thāniya, which is not only ‘second’ as a noun but also as a numeral. Comparing all these words closely, we see that the meaning of the Latin minuta is particularly similar to the Arabic word: in these two languages, but not in Greek, it refers to something ‘small’. It stands to reason therefore that minuta is not so much a calque from Greek as from Arabic. There you have it: elements from three major languages in these two seemingly unremarkable words.
One last thing. In Modern Greek, a ‘minute’ is called lepto and a ‘second’ deuterolepto (or strictly speaking defterolepto). Literally, these words mean ‘something small’ and ‘a second something small’ (sorry for the bad grammar). Obviously, these are yet again calques, undoubtedly from Latin. But calque upon calque upon calque has made Ptolemy’s original practically unrecognisable. The concept has come full circle, from Greek to Greek, but the words have taken a serious pummelling.
* For Ptolemy, minutes (and also seconds) were essentially minutes of arc, that is parts of a degree, not of an hour – I’m not sure if he ever used the word in a temporal sense. However, both types of minutes are more closely related than they may seem at first sight: in sundials, it’s the angle between the visible shadow of the so-called gnomon and its shadow at noon that indicates the current time. A 15 degree angle is equivalent to one hour, so there’s 15 minutes of arc to the clock minute. Why is that? I have no idea.