ad hominemadjective
/ˌædˈhɒm.ɪ.nəm/formal(of a criticism, etc.) directed against a person, rather than against what that person is saying:
an ad hominem attack on his rival
ad hominem
adverb /ˌædˈhɒm.ɪ.nəm/formal
They accused her of arguing ad hominem.