陰性

1. Origins, structure, and basic meaning

• Structure: 陰性(いんせい) is a test finding in which the reaction or sign being tested for was not detected.
• Basic usage: It describes being told by a doctor to rest at home because the test result was negative.
  • 検査結果は陰性だったので、医師から自宅で休むよう言われた。

2. Common pitfalls and similar expressions

• The opposite finding and the word's scope
  • In a testing context, the opposite is 陽性(ようせい). 陰性 and 陽性 label findings about the tested reaction rather than expressing an emotional judgment that a result is good or bad.