"Bo" is a pictophonetic character, and the initials are pictophonetic characters. Take a person's head as an example, one word can prove it. Oracle Bone Inscriptions and Jinwen are shown in white. The combination of seal script and signifier makes people understand from white that white is also a sound. Regular script writing after the official reform. It is the original word of "ba". The original meaning is human head. Extended refers to the leader, and Oracle Bone Inscriptions cloud refers to the "white" leader.
Uncle, read Bobo in written language. Used as a title for father and brother; Also used for uncle, as a title for an older man of his father's generation. In Hong Kong and Macau, if a man is called an uncle, it may cause the other person's displeasure. In Hong Kong and Macau, it is customary to call women ladies and men gentlemen. Uncle usually calls his father's brother uncle, and in the old society, he was also called father, which is often used as a friendly title between friends. In a few areas, older women are also called uncles, which is just a representative title, regardless of age and status.
General usage of "uncle":
When related by blood: generally, it is only called father and brother, and uncle is a kind of kinship title, which refers to the father's brother, also called uncle or uncle, or uncle for short. In ancient times, I was called from my father. But "bo (bǐ i)" can also refer to brother-in-law, that is, the husband's brother. My uncle's wife's name is Bom or Auntie or Auntie. When there is no blood relationship: "Uncle", "Uncle" and "Qiaomu" can also be called male elders older than their father, or honorifics for friends' fathers, such as "Shibo".
"Uncle" and "Aber" are also appellations for middle-aged and elderly men. It's not that strict. It doesn't mean that people older than their father must be called uncles. It is also ok to call someone one or two years older than his father or three or four years old "uncle"; And uncle sounds young and says uncle looks old. Now we call the old man uncle outside, and uncle has become a kind of honorific title, instead of carefully studying who is older and younger than father.