I wish I could remember where I heard this word. Unfortunately, I just have the word written down and the definition (and under that, a game of まるばつ aka Tic Tac To, which I played with my host sister. Not sure if they have any connection...)
This will come in handy if you want to relate a story about being pestered. You can say something like:
お金を貸してとねだった・おかねをかしてとねだった He kept bugging me to lend him money.
部屋をそうじしてとねだる母・へやをそうじしてとねだるはは A mother who nags you to clean your room.
あのこっていつもこっちみてとねだっている That kid is always pestering me to look over at him.
This format is basically "Direct quote" quotative marker verb, so it's an easy one to use and remember! Being pestered isn't too fun, though, so hopefully you won't have too much occasion to use it.