How to display the "left hand" radical as Unicode text?
Just FYI, the top left part of「右」and the top left part of「左」have different origins. Also, neither of them have anything to do with「十」.



The top left part of「右」as a stand-alone character is now written as「又」. It was originally a picture of a right hand.

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The「口」in「右」was added later to distinguish between the meaning right hand (anatomy) and right side.

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The top left part of「左」, unsurprisingly, was originally a picture of a left hand. As a stand-alone character, it is now written as「」.

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The「工」(picture of a tool) in「左」was added later to bring out the meaning of assistance, help, now written as「佐」.

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The top left component of「右」and「左」look very similar in the modern script, but the original components meant different things and had different pronunciations. For example,「又」, being the top left component of「右」, is also found at the top left part of both of the following characters, where it contributes both meaning and sound:


「有」(yǒu; picture of a hand「又」yòu holding a piece of meat「⺼・肉」> to have [something])
「友」(yǒu; picture of two right hands「又」yòu > friend)




References:


小學堂
國學大師


郭沫若《甲骨文合集》
中國社會科學院考古研究所《殷周金文集成》