ignoratio elenchi
Concise Oxford English Dictionary © 2008 Oxford University Press:
ignoratio elenchi /ˌɪgnəˈreɪʃɪəʊ ɪˈlɛŋkʌɪ/
▶noun (pl. ignorationes elenchi /-ˈəʊniːz/) Philosophy a logical fallacy which consists in apparently refuting an opponent while actually disproving something not asserted.
– origin L., lit. ‘ignorance of the elenchus’.
'ignoratio elenchi' also found in these Oxford entries:

