Why is there an “al” in algebra?

Question

Words like "algebra", "alchemy" and "alcohol" were introduced to English via Arabic. The "al-" prefix is the Arabic definite article. Why was the definite article retained when the words were incorporated into English?

BTW: I am aware that Arabic was not the origin of some of these words but it did add the "al-" prefix.

Answer 1

In Arabic, the definite article is always prefixed, never standing on its own as a word. Thus, the original Arabic word الجبر (transliterated al-jabr) became Latin algebra.

Answer 2

All three words have Arabic origins, but they entered English via other languages which had already imported the definite article with them.

Answer 3

The Arabic indefinite article is not recognized as such by the foreign listener. To a foreign speaker the 'al-' sounds like it is part of the original word, it is not obvious that it is an article, and so is not something that is translated. The entire sound is considered a new word.

That is the general rule for borrowing from another language.

In the particular instances you give, for 'al-' from Arabic, they are almost entirely borrowed from an intermediate language (Spanish, French or Latin) which already made the foreign (Arabic) article part of the word.

Answer 4

On this matter it is interesting to read the following piece¹.

It is instructive to consider some of the words that we derive from Arabic, such as: algebra, alcohol, alchemy, alembic, alkali, azimuth, zenith. With the exception of "alcohol"—which meant, not a drink, but a substance used in chemistry—these words would give a good picture of some of the things we owe to the Arabs. Algebra had been invented by the Alexandrian Greeks, but was carried further by the Mohammedans. "Alchemy,” "alembic," "alkali" are words connected with the attempt to turn base metals into gold, which the Arabs took over from the Greeks, and in pursuit of which they appealed to Greek philosophy. "Azimuth" and "zenith" are astronomical terms, chiefly useful to the Arabs in connection with astrology.

The etymological method conceals what we owe to the Arabs as regards knowledge of Greek philosophy, because, when it was again studied in Europe, the technical terms required were taken from Greek or Latin. In philosophy, the Arabs were better as commentators than as original thinkers.

Their importance, for us, is that they, and not the Christians, were the immediate inheritors of those parts of the Greek tradition which only the Eastern Empire had kept alive. Contact with the Mohammedans, in Spain, and to a lesser extent in Sicily, made the West aware of Aristotle; also of Arabic numerals, algebra, and chemistry. It was this contact that began the revival of learning in the eleventh century, leading to the Scholastic philosophy. It was later, from the thirteenth century onward, that the study of Greek enabled men to go direct to the works of Plato and Aristotle and other Greek writers of antiquity. But if the Arabs had not preserved the tradition, the men of the Renaissance might not have suspected how much was to be gained by the revival of classical learning.

¹ _{History of Western Philosophy, by Bertrand Russell}