The term alipin refers to the lowest social class among the various cultures of the Philippines before the arrival of the Spanish in the 16th and 17th centuries. The closest and most common translation of the word is "servant" or "slave", as opposed to the higher classes of the Timawa (Freemen) and the Maginoo (Noblemen). An alipin can also buy his own freedom by marrying a timawa. A timawa is of higher class than the alipin. They can also gain their freedom if their masters set them free. Other alipin are too old and are long in service which gives them retirement freedom. Others stay with their masters until their near death†.
While the alipin does, indeed, serve another person, historians note that translating the term as "slave" in the western sense of the word may not be fully justifiable. Documented observations from the 17th century indicate that there may be significant differences between the Western concept of "slave" and the Pre-Hispanic Filipino concept of "alipin".
As a social class, "alipin" had subclasses as well, documented by numerous Spanish historians, who took note of the local social norms as the Spanish conquest of the Philippines began.