The Shuowen Jiezi interprets "yuan" as "yuan, beginning also." From one from the Vultures". In fact, the interpretation of the Shuowen is not the original meaning of "yuan", but the extended meaning, and its original meaning is "human head".
First, the original meaning is "human head"
It can be confirmed in the oracle bones and gold texts of the Shang Zhou Dynasty, such as the Shang Dynasty Jin glyph writing:

Screenshot from "Chinese Character Holographic Resource System"
The upper part is a round human head, and in order to highlight the human head, the side-standing human body is drawn with the lower part of the glyph. as:
Screenshot from "500 Cases of Chinese Character Evolution"
In the oracle bone, in order to facilitate the engraving, some of the upper round heads are only outlined (circled in the following figure), or even simplified to one or two horizontal, so such a glyph appears.
There was no difference between one horizontal and two horizontals on the side of the human form, both were "yuan" characters that expressed the meaning of "human head", but later the horizontal differentiation became the "Wu" character of "Wu Zi", and the two horizontal ones became the "Yuan" characters of the table head.
Second, the original meaning is an example of "human head"
The original meaning of the word "yuan" is "human head" as exemplified in ancient texts. For example, the "Yuan" in "Zuo Chuan , Three Years of Gong Gong" "Di Ren Returns to His Yuan, Face Like Life". Another example is the "Yuan" character in "Mencius Teng Wen Gongxia" "The warrior does not forget (Note: tong death, avoid) mourning his yuan". Both "yuan" characters are used in the original meaning of "human head".
In the ancient characters of the Yuan, we can also find example characters that are originally meaning "human head", such as the word "Kou", and the ancient characters are as follows.
Jin Wen "Kou" character, "Chinese Character Origin And Flow" 17 pages
The word "Kou" indicates that a mob invaded the room and struck people on the head with weapons, which is used to indicate invasion and theft.
For another example, the "crown" spoken of as a hat, in the Chu character of the Warring States, the word "crown" is also from the yuan, and the yuan from which it is also related to the meaning of "human head", as shown in the figure.
The word "crown" in the Warring States Chu script, Shuowen Xinzheng, p. 632
In addition, two words with similar meanings form a word are more common in modern Chinese vocabulary. In the modern Chinese vocabulary "fuehrer", the ancient glyph of the word "shou" is the side view of the human head, as shown below, which also proves that the original meaning of the "yuan" character is "human head".
Oracle "first" character, "Chinese Character Origin And Flow", p. 49
Later, the word "Fuehrer" was used to mean "the supreme leader of the country".
III. Extension of the word "Yuan" and "Yuan Lai"
Derived from the original meaning of the word "yuan", the extended meaning of "beginning, first". It is the same as the "yuan" interpreted in the Shuowen Jiezi. Therefore, in modern Chinese vocabulary, there are words such as "Yuan Shi, New Year's Day, Yuan Yue, Yuan Nian" and so on.
Even the modern Chinese word "yuan" was written "Yuanlai" before the Ming Dynasty, and the "Yuan" in "Yuanlai" was also used in its extended meaning. After the Ming Dynasty inherited the Yuan Dynasty, it was afraid that people would misunderstand the "Yuan" of "Yuan Lai" and "Yuan Yu" as the "Yuan" of the Yuan Dynasty, so they replaced "Yuan" with "Yuan".
Fourth, the "Yuan" character inscription is appreciated with words
The word "yuan" is a very commonly used word, and there are many "yuan" characters in the ancient inscriptions, and there are several for everyone to enjoy.
Seal book, from the "Explanation of Words": ↓↓
Lishu, from the Cao Quan Stele: ↓↓
Lishu, from the "Ceremonial Stele": ↓↓
Lishu, from the "Yi Ying Stele": ↓↓
Xingkai, from Yan Zhenqing's "Sacrifice nephew draft": ↓↓
XingKai, from Mi Fu's "Shu Su Ti": ↓↓
Wei Bei, from the "Portrait of a Buddha": ↓↓
Letter of Letters, from Ouyang Inquiry's "Jiucheng Palace": ↓↓
Italics, from Yu Shinan's "Monument to the Temple of Confucius": ↓↓
Italics, from Liu Gongquan's "Xuan secret pagoda stele": ↓↓
5. Summary
The original meaning of the word "yuan" is "human head", and the meaning of "beginning, first" is its extended meaning.
The original meaning of the word "yuan" is "human head", which can be confirmed in ancient texts and ancient glyphs from the Yuan (such as "Kou" and "Guan"), and can also be confirmed in the modern Chinese word "Fuehrer".
The word "original" is originally written as "Yuan Lai".
The Chinese characters in the inscriptions are also mesmerizing, and the Chinese characters are "drunk" beautiful!