Russian to English Art/Literary General / Conversation / Greetings / Letters Talking with children

I can't tell if I just don't know this word, or if it's dialect, or if the speaker is distorting it because he's talking to a child. An old Jewish grandfather in Tashkent, 1960s, says to his two-year-old grandson, "Юра, нагзи-и"?

And then it continues, "Дед любил пошутить с малышами. Слово 'нагзи' произносилось им с долгим гортанным г и с длинным и. При этом лицо его становилось удивительно смешным...." - and then the little boy gets interested in Grandpa's beard because it sticks out as he makes this facial expression. The grandfather is in the courtyard, the grandson is inside the house, looking out the window at grandpa and trying to reach him through the fortochka.

There are Tajik phrases scattered in this passage, but they are all translated, and this is not. That makes me think it's "baby talk," but I don't catch it.