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determined; single-minded; intent; desperate; wild
「一向」 has another reading with different meanings.
一向に信心を貫いた僧侶だった。
He was a monk who single-mindedly upheld his faith.
一向な思いで修行に励んだ。
He devoted himself to training with determined spirit.
一向に前を向いて歩き続けた。
He kept walking forward with single-minded determination.