With regard to 'Muchimi' (ムチミ) - 'heaviness', 'rooted':
When I was younger (and less experienced in translation), I probably would have been tempted to read the Japanese (Katakana) character of 'チ' (chi) - or 'one thousand' - as being related to the Chinese ideogram of '手' (shou3) - meaning 'open hand' (and to 'clutch', etc), as they look very similar in structure. My instinct would have led me in this direction considering the martial arts usage related with the term 'Muchimi' - applying a logical 'reverse chain of events', so-to-speak (in other words - 'working backwards' using logical association). However, all the multi-language dictionaries I have access to today - strongly suggest there is no connection between these two characters.
As this possible association played on my mind (in the sense that no stone should remain unturned), I checked '手' (shou3) in these dictionaries (focusing on the 'Japanese' variants) and found that even today - the Chinese ideogram of '手' is still often used - 'unchanged' - within Japanese script, usually rendered as 'te' or 'shu', etc. When '手' is modified within Japanese script - it is presented as 'テ' (Katakana) and 'て' (Hiragana) - pronounced 'te' and 'shu' respectively.
Therefore, although the 'チ' (Katakana) character found within 'Muchimi' (meaning 'one thousand') is 'similar' to the (Katakana) character 'テ' (te) - meaning 'open hand' - as you can see, there are slightly different upper structural differences - despite a certain lower level similarity. After further studying the history of each of these specific Japanese (Katakana) characters - the lower similarity appears to be purely coincidental rather than deliberate. The conclusion being that there is no connection between the 'チ' (Chi) - one thousand -Japanese (Katakana) character and the '手' (shou3) - meaning 'open hand' - Chinese ideogram.
Best Wishes
Adrian