[ Source : ] Interestingly, anakrouein or anacrusis is also found in Greek poetry, where the first syllable is not accented. Being the sea-faring people as they were, starting a poem with anacrusis felt like pushing a ship back from the dock, signalling a start of a voyage.
I don't understand the last sentence overhead. I don't know about Ancient Greek marine navigation, but I'd divine that ships don't always reverse when leaving port? They can leave by dock by going forward and turning away?
TL;DR: The quoted claim seems to be a speculation or flight of fancy based on a linguistic coincidence.
In classical Greek, ἀνάκρουσις has two senses, according to Liddell and Scott (1889), A Greek-English Lexicon:
pushing back, especially pushing a ship back, backing water; of a horse, with the bit: metaphorically, reaction against depression; return.
in Music, first beginning of a tune
In English, the word has another meaning. According to the Oxford English Dictionary:
anacrusis, n. ‘A syllable at the beginning of a verse before the just rhythm’ (Kennedy).
This sense of the word was coined by philologist Johann Gottfried Jakob Hermann in Elementa Doctrinae Metricae (‘elements of the doctrine of metres’), 1817. See here for its first appearance in Hermann’s original Latin, and here for the 1830 English translation by John Seager.
A couple of sources for my claim that it was coined by Hermann:
In such metres the first arsis was by Hermann called the “anacrusis,” a name which has been adopted by other modern writers. [William Smith (1890). A Dictionary of Greek and Roman Antiquities. London: John Murray.]
So far as I am aware, anacrusis is not mentioned by an ancient metrist, but is an "invention" of Hermann. [Richard Wellington Husband (1914). ‘The Old and the New in Metrics’. The Classical Journal 9:5 pp. 212–221.]
It should be remembered that ancient Greek ships were galleys: they could sail if winds were favourable, but under other conditions they were powered by oars. In oared vessels, to back water means to reverse the action of the oars so that the vessel reverses direction without turning.
Let's have a look at the sources to see how this sense of ἀνάκρουσις was employed.
Herodotus, Histories, in a description of the battle of Salamis, 480 BCE:
8.84.2 The Athenians say that the fighting at sea began this way, but the Aeginetans say that the ship which had been sent to Aegina after the sons of Aeacus was the one that started it. The story is also told that the phantom of a woman appeared to them, who cried commands loud enough for all the Hellenic fleet to hear, reproaching them first with, “Men possessed, how long will you still be backing water?” [Translation by A. D. Godley, 1920.]
Diodorus Siculus, Bibliotheca historica, in another description of the battle of Salamis:
11.18.6 The Athenians, observing the disorder among the barbarians, now advanced upon the enemy, and some of their ships they struck with their rams, while from others they sheared off the rows of oars; and when the men at the oars could no longer do their work, many Persian triremes, getting sidewise to the enemy, were time and again severely damaged by the beaks of the ships. Consequently they ceased merely backing water, but turned about and fled precipitately. [Translation by C. H. Oldfather, 1989.]
Thucydides, History of the Peloponnesian War, in an account of the second battle of Syracuse in 414 BCE, in which the Syracusan fleet was able to trap the Athenian ships in the harbour of Syracuse and push them onto shore:
7.36.5 This charging prow to prow which had hitherto been thought want of skill in a helmsman, would be the Syracusans' chief manoeuvre, as being that which they should find most useful, since the Athenians, if repulsed, would not be able to back water in any direction except towards the shore, and that only for a little way, and in the little space in front of their own camp. The rest of the harbor would be commanded by the Syracusans; 7.36.6 and the Athenians, if hard pressed, by crowding together in a small space and all to the same point, would run foul of one another and fall into disorder, which was, in fact, the thing that did the Athenians most harm in all the sea-fights, they not having, like the Syracusans, the whole harbor to retreat over. As to their sailing round into the open sea, this would be impossible, with the Syracusans in possession of the way out and in, especially as Plemmyrium would be hostile to them, and the mouth of the harbor was not large. [Translation by Richard Crawley, 1910.]
And in a speech by Nicias in which he is trying to encourage the Athenians after their defeat at sea:
7.62.3 We have also discovered the changes in construction that we must make to meet theirs; and against the thickness of their cheeks, which did us the greatest mischief, we have provided grappling-irons, which will prevent an assailant backing water after charging, if the soldiers on deck here do their duty;
It appears that the military problem was that the Syracusans, with their heavier but less numerous ships, were able to ram the Athenian ships, and then back water in order to gain space to make another ramming attempt. Application of grappling hooks would prevent this manoeuvre and force the Syracusans to engage in hand-to-hand fighting on the decks of the two entangled ships.
I can find no evidence for the claims quoted in the post:
There is no evidence that classical Greeks described an unaccented initial syllable as an anacrusis. This sense of the word is a 19th-century coinage by Hermann.
There is no evidence that classical Greeks used the word anacrusis to describe the start of a voyage. All the uses that I was able to find are in the context of naval warfare, and describe reversing oars in order to retreat from contact with an enemy.
As the other answer says, the word anacrusis for a preliminary unaccented syllable seems to have been invented by Johann Gottfried Jakob Hermann. Besides backing water, there may be another possible place where Hermann could have gotten the name from.
Looking in a French dictionary at the etymology of anacrouse, they pointed me to the Pythian games—contests held in Delphi every four years, honoring the God Apollo.
There was a very specific musical contest in these games.
I then found a description of the relevant contest in the Pythian games in a translation of Strabo's Geography. This is the only place I can find where this contest was described, and thus if the contest is where Hermann got the name, he probably found it in Strabo.
Strabo was a Greek geographer and historian who lived in the first century BCE. The following sentences (which are nearly the only relevant material) are an excerpt from Strabo:
There was anciently a contest held at Delphi, of players on the cithara, who executed a pan in honour of the god.
...
The players on the cithara were accompanied by players on the flute, and by citharists, who performed without singing. They performed a strain (Melos), called the Pythian mood (Nomos). It consisted of five parts; the anacrusis, the ampeira, cataceleusmus, iambics and dactyls, and pipes.
So the ancient greeks indeed seem to have used ἀνάκρουσις for the first movement of a musical composition, or at least for this specific musical composition in the Pythian games. Although this is somewhat different than the meaning Johann Hermann (see the other answer) assigned it in 1817, one can see why Johann Hermann might have chosen anacrusis for this meaning.
Why was anacrusis used for the first movement of the composition in the Pythian games, and did this have anything to do with its use in sea battles? I don't know. But certainly the idea that starting a song with a few unaccented syllables is like pushing a ship back from the docks seems to be an invented etymology.
