This is the 10781st most frequent Turkish word.
demedik
"Demedik" means "we/they did not say" in English.
Here, 'demedik' is used with the personal pronoun 'ben' to indicate something that was never said by the speaker.
Ben onu hiç demedik.
I never said that.
In this sentence, 'demedik' refers to something not said by the addressed group ('siz'), forming a rhetorical question.
Siz böyle bir şey demedik, değil mi?
You didn't say such a thing, did you?
Here, 'demediklerini' (a derivative form of 'demedik') is used to refer to things that they didn't say, linking past and present events.