Is the difference in "sake" in English and Japanese a form of semantic change?

Solution 1:

This phenomenon is fairly common, and can be called "semantic change" or more specifically "semantic narrowing". It is one of many patterns that crop up when a word is imported from one language to another.

Using sake for the fermented rice drink reflects the fact that it is a drink that English-speaking people had not previously encountered. It is one of the earliest words to be received into English from Japanese - the OED traces it to 1687, in an English translation of a French traveller's book (The travels of monsieur de Thévenot into the Levant):

Their ordinary drink is a kind of Beer (which they call Saque) made of Rice.

From the citations there, it seems that sake in English has consistently meant the same thing since its original borrowing.

The Japanese contributions to the English language: an historical dictionary (Garland Cannon, 1996) suggests that British travellers in this period "generally showed little interest in learning Japanese" and that although they ate the local food, they would typically speak and write of it using English words. Consequently, the Japanese words would tend to be applied for foods (or other things) that had no clear Western equivalent, or were in some way distinctively Japanese.

Example borrowings from the same period include food words like miso and soy, political terms like daimyo and shogun, and names for Japanese plants, furniture, swords (katana), clothing (kimono), and so on.

Solution 2:

I would consider it an "error in translation". Consider the first time a Westerner dropped anchor in Japan. He'd be greeted, and possibly given a bowl of something to drink. He'd ask, "what is this?", and be told "sake". The "sake" in this case might have happened to be rice wine (Nihonshu) instead of other spirits common in feudal Japan such as plum wine (Ume). As that specific drink became popular it simply became known as "sake".

This has occurred many times throughout history. English explorers and colonists point, ask, and get a mouthful of syllables, which becomes the name of the whatzit. Usually, the term in its native tongue has a semantic difference; similar to "sake", "schnapps" is simply German for "strong liquor", which in native use could be anything from Jager to Scotch to cognac, but in English has become more specific to German liquors or to nondescript flavored liquors. It can go the other way too; the word "kangaroo" was derived from the native ganguruu for a specific species, the grey kangaroo, but now applies to all species of the Macropodidae family. The urban legend that "Kangaroo" is native for "I don't know" is exactly that, but it's certainly plausible, whether it's happened or not, that somewhere along the way a name for something was derived from the native for "why do you ask?".