adjective
[ only before noun ] ( disapproving ) produced automatically, without any serious thought :
It was a knee-jerk reaction on her part.
adjective
[ only before noun ] ( disapproving ) produced automatically, without any serious thought :
It was a knee-jerk reaction on her part.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005