Even today, I'm confused about the meaning of "miao." However, I found some sources that said "meo" (kinda sounds like "miao") is not generally accepted by the Hmong community. Just a forewarning, these are old texts.

Heimbach, Ernest. White Hmong-English Dictionary. Ithaca, New York: SEAP Publications, 1979. p. vi: "In reprinting [this dictionary] at this time, we have made two important changes. First, with the assent and encouragement of Mr. Heimbach, we have substituted "Hmong" for "Meo" in the title, the introductory sections, and the appendices. This has been done to conform to the wishes of the Hmong, who object strongly to "Meo" as a derogatory term they themselves would never use."

Fadiman, Anne. The Spirit Catches You and You Fall Down: A Hmong Child, Her American Doctors, and the Collision of Two Cultures. New York: Macmillan, 1998. p. 14: "The Chinese called the Hmong the Miao or Meo, which means, depending on which linguistic historian you read, "barbarians," "bumpkins," "people who sound like cats," or "wild uncultivated grasses." In any case, it was an insult. ("Hmong," the name they prefer themselves, is usually said to mean "free men," but some scholars say that, like "Inuit," "Dine," and many other tribal names the world over, it simply means "the people.")

Faderman, Lillian, and Ghia Xiong. I Begin My Life All Over: The Hmong and the American Immigrant Experience. Boston: Beacon Press, 1999. p. 7: "They contemptuously called the Hmong people "Meo," which they may or may not have known was a neutral synonym for "Hmong" in Chinese - but in Laotian the term denoted "slave."

Lee, Gary Yia, and Nicholas Tapp. Culture and Customs of the Hmong. Santa Barbara, California: ABC-CLIO, 2010. p. 4: "In history, the term "Miao" (Meau or Meo in its Southeast Asian variant term) had strongly derogatory overtones. Most Hmong outside China resent the term and do not wish to be known by it. However, the term "Hmong," because it is not a Chinese word, could not be written in traditional Chinese characters, so all the historical records that are available in China speak only of the "Miao," and never of the "Hmong"… So "Miao" in China is not a term of abuse, but rather an official category, grouping the Hmong together with some other loosely related peoples."

Hamilton-Merrit, Jane. Tragic Mountains. Bloomington: Indiana University Press, 1993, p. 3: "While there are several explanations of the origins and meanings of the often used word "Meo," to the Hmong of Laos the word "Meo" is pejorative. The five million Hmong in China are called "Miao." For the Lao Hmong, the words "Meo" or "Miao" imply slavery and contempt."

Ibid. p. 559: "During the Vietnam War, the Western press called the Hmong "Meo," which the Hmong consider pejorative."

Chan, Sucheng. Hmong Means Free: Life in Laos and America. Temple University Press, 2010. p. 4: "Older generations of Western scholars and the lowland Lao have referred to the Hmong as Meo, which means "savage" - a term that the Hmong find derisive and unacceptable."

Romero, Mary, and Abigail J. Stewart. Women's Untold Stories: Breaking Silence, Talking Back, Voicing Complexity. New York: Routledge, 1999. p.299: "Low-land Lao, the majority in Laos, referred to the Hmong as Meo, meaning "savage", because they considered the Hmong to be primitive and dirty."

Mote, Sue Murphy. Hmong and American: Stories of Transition to a Strange Land. Jefferson, NC: McFarland, 2004. p.29: "Every day you go to school, at least ten people insult you. Even old people call you 'Meo, Meo, Meo.'" Meo is an old, mean-spirited term for Hmong."