Proclaim!
In the name of thy Lord and Cherisher, who created -
created man, out of a mere clot of congealed blood.
-- Sura 96:1-2
The Arabic word used by the Qur'an which has generally been translated as "a clot of blood", is "`alaq" . The meaning of this word is given by "Qaamoos al-Muheet" as:
Blood in its normal state or blood which is extremely red or which has hardened or congealed, a piece thereof; every thing that sticks; clay that sticks to hands; unchanging enmity or love; Zu `alaq is the name of a hill of Banu Asad, where they defeated Rabi`ah ibn Maalik; An insect of water that sucks blood; that portion of a tree that is within the reach of animals.
The word `alaq, does not "mean" blood but because of certain properties of blood, it was, besides other things also used to imply blood. The real meaning of the word, as would be obvious from an analysis of all the meanings stated above, is anything that sticks to or hangs with something else. The word was used for blood, because of the well known property of blood of being sticky, as soon as its starts to dry out. The word was used for mud, because of its obvious property of sticking to the hands. The word was used for unending hatred or love, because such emotions stick to one's heart. The word was used for a small insect which sucks blood (leech), because it sticks to its prey. The word was also used for that part of the tree, which is in the reach of grazing animals, becuse the animals stick to that part of it.
Thus, the real meaning of the word "`alaq" is "anything that sticks or hangs". Now when the Qur'an said: "He created man of `alaq", it was interpreted by Muslim scholars to imply "a clot of blood". This was not because the word "`alaq" meant "a clot of blood" but because the Muslim scholars felt that in this verse it implied "a clot of blood". If, due to the widening of human knowledge, today we are in a position to know that a child is never "a clot of blood", all that has happened is that we can now safely say that the interpretation of the Muslim scholars was not accurate. If the Qur'an was not available in its original language, as is generally the case with the books, other than the Qur'an, believed to be revealed literature, the Muslims would have had no option but to submit that the Qur'an does have a "scientific error" in it. But the case of the Qur'an is quite different from those other books. It is still in its original language. And the word originally used by the Qur'an (`alaq) is not used only for a clot of blood. It actually refers to "something that sticks" (like semi dried blood, mud, unending hatred/love or a leech).