na-adjective
analgesic; pain-relieving
Medical term used to describe drugs, treatments, or effects that relieve pain. Often appears in compound nouns like 鎮痛性薬剤 (analgesic agent).
この薬には鎮痛性の成分が含まれている。
This medicine contains analgesic ingredients.
鎮痛性のある湿布を貼
I applied a pain-relieving compress.
Compound of 鎮痛 (pain relief) + 性 (property/nature). The exact historical derivation is uncertain; the spelling is conventionally associated with medical terminology.