NK細胞えぬけーさいぼうMeanings1nounnatural killer cell; NK cellbiology›Biology term for a type of lymphocyte that can kill virus-infected cells and tumor cells without prior sensitization.See also: ナチュラルキラー細胞NK細さい胞ぼうは、ウイルス感かん染せん細さい胞ぼうを攻こう撃げきする免めん疫えき細さい胞ぼうの一いっ種しゅです。NK cells are a type of immune cell that attacks virus-infected cells.