(へんしつ)

へんしつ
noun, suru verb
change in quality, deterioration, alteration
1. change in quality, deterioration, alteration
A change in the fundamental nature or quality of something, usually for the worse. Used for physical substances (food spoilage, chemical changes) and abstract concepts (character, nature of an organization).
食品(しょくひん)変質(へんしつ)した。
The food deteriorated in quality.
高温(こうおん)多湿(たしつ)環境(かんきょう)では(くすり)変質(へんしつ)しやすい。
Medicines are prone to deterioration in hot and humid environments.
長年(ながねん)のうちに組織(そしき)性格(せいかく)変質(へんしつ)し、当初(とうしょ)理念(りねん)(うしな)われた。
Over the years, the character of the organization changed, and its original ideals were lost.

USAGE:
Often carries a negative connotation, implying degradation rather than improvement. For physical substances, it suggests spoilage or chemical breakdown. For abstract concepts, it suggests corruption or loss of original character.

RELATED WORDS:
変質者(へんしつしゃ) means a pervert or deviant — a completely different usage from the base word. This compound should not be confused with the general meaning of 変質(へんしつ).

COMMON COLLOCATIONS:

  • 変質(へんしつ)する: to deteriorate, to undergo a change in quality
  • 変質(へんしつ)(ふせ)ぐ: to prevent deterioration
  • 変質(へんしつ)防止(ぼうし): prevention of deterioration