Xing Yi Quan in Chinese / Japanese...

形意拳 is the title for the Xingyiquan style/form of Chinese martial arts involving explosive linear movements.

Some translate this as “shape-of-the-mind fist.”

While pronunciation has never changed in Chinese, the old romanization was “Hsing I Chuan.” This romanization for 形意拳 is still used in Taiwan.

This term is used in some Japanese martial arts circles where it's romanized from Japanese as keīken, keiiken, or keiken.