Mulatto, we all know what it means. If you're not big on multiracial issues, then I suppose I can give you the Merriam-Webster definition and etymology:

Function:
noun
Inflected Form(s):
plural mu·lat·toes or mu·lat·tos
Etymology:
Spanish mulato, from mulo mule, from Latin mulus
Date:
1593

1 : the first-generation offspring of a black person and a white person \
2 : a person of mixed white and black ancestry

As to be expected, Webster only reports the term's meaning (duh, it's a dictionary). So, I suppose we'll derive how this word may even be considered offensive to some today by starting with the etymology of mulatto.

The Spanish mulato is derived from mulo/mule. This mule, produced from a male donkey (62 chromosomes) and a female horse (64 chromosomes) has 63 chromosomes. This resulting number of chromosomes inhibits sterility in mules over 99.99% of the time (there have been a few documented cases of sterile female mules). Back during slavery times, many people operated around the paradigm that black people and white people were different species to say the least. Thus, when a mulatto was born to a black parent and white parent it was believed to be sterile like mules. It is hard for me to believe that people actually believed this phenom after the first couple of decades of its inception, because naturally mulattoes would go on to produce children with white, black, and other mulatto people. So, was it used as a constant reminder that these children spawned from two diametric forces were too different to be accepted anywhere or did bad habits just die hard?

While some people did harbor these absurdities that mulattoes were sterile, it's hard to believe that the majority of the people (whether they were racist or not) would continue believing a proven falsity. Mulatto was continually used as a description for black/white biracials until the 1930 census. By this time, mulattoes were already "successfully forced" into a Negro identity thus restoring the black-white "color" line. Now that we know the history of mulatto, is it socially acceptable to be used? It is the most accurate description of a half-white/half-black person; however, its history does carry a lot of weight.

I think that if a person wants to be empowered through the description mulatto, then that person should be respected. Just take a look at the word nigga. Many African-Americans have turned the most heinous of words into a term of endearment. Quite naturally, I don't see why mulattoes cannot do the same. Opponents would suggest just calling these individuals solely biracial. But what does biracial even mean? Exactly, it can mean a myriad of things. Again, if someone wants to be called a mulatto then more power to him/her. Or they can be solely called black.

Daimian, Chameleon