How to say "reflexes" in Japanese

• 反射はんしゃJLPT N1approx.Common
  nounCovers reflexes as automatic, involuntary responses of the body or nervous system, such as a knee-jerk reaction. It refers to the physiological mechanism itself, not to overall athletic quickness.
• 運動神経うんどうしんけいCommon
  nounUsed for reflexes in the everyday sense of being quick or clumsy in physical reactions; it really means athletic ability or motor coordination, as in praising someone's reflexes in sports.
  お兄にいさんと比くらべて、彼かれは運動うんどう神経しんけいが鈍にぶい。↗

  Compared with his brother, he is a poor athlete.

Use 反射 for reflexes as automatic physical or psychological responses, and 運動神経 when talking about someone's quickness, athletic ability, or motor coordination.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 反射神経はんしゃしんけいreflexes
• 反射はんしゃreflex
• 運動神経うんどうしんけいreflexes