How would you translate "grit" (personality trait) to Chinese? According to psychologist Angela Duckworth and colleagues, "grit" is defined as "perseverance and passion for long-term goals".

What would be the closest term for "grit" in Chinese?

Google gives me "sand" and "gravel" as its meaning.

砂砾 (shālì) = gravel
沙子 (shāzi) = sand
粗砂石 (cū shā shí) = coarse sandstone

Thanks, Nate
PS. I've also inquired Professor Duckworth and still waiting for her response.
毅力 (n)
perserverance; willpower
He has grit = 他有毅力

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堅毅 (adj)
be strong-willed and perseverant
He is very gritty = 他很堅毅

~

堅毅 (n)
strong will and perserverance
This grittiness = 這份堅毅

Example sentence:

推行革命要有毅力 - Carrying out the revolution requires perseverance (grit)

堅毅的人能衝出困境，走向高峯 - perseverant (gritty) people can break out of  predicament and get to the top

成功全憑民眾的一股毅力/成功全憑民眾的一份堅毅 - Success depends on the perseverance (grittiness) of the people