To beg or pester someone persistently in order to obtain something; to coax or importune (often written in kana).
子どもが何度もおもちゃをねだっている。
A child is repeatedly begging for a toy.
彼は友達に金をねだって断られた。
He begged his friend for money but was refused.
セールで安くしてほしいと店員にねだるのは失礼だ。
It's rude to pester a clerk to lower the price during a sale.
彼女はデートの約束をしつこくねだった。
She persistently begged him for a date.