Nweke injured her knee in the Ferns pool match against Singapore with the team's medical staff confirming today that scans have revealed a partial tear in her patella tendon.
Travelling reserve Tiana Metuarau has been called into the playing 12 for the remainder of the tournament.
Silver Ferns head coach Dame Noeline Taurua said it was a gutting blow for both Grace and the team.
"Obviously we are hugely disappointed for Grace who was competing at her first Netball World Cup, she provides a unique skill set for our team and will be massively missed," she said.
"The positive is that being able to carry travelling reserves to this Netball World Cup means we are able to bring Tiana in, who has been training with us throughout our build-up and is familiar with our structures and the players around her.
"This is not a scenario we were wanting but we are as prepared for it as we can be and move on to the next stage of the Netball World Cup and our match against Wales."
The Silver Ferns take on Wales in their first crossover match at 9pm tonight (NZT) ahead of a rest day before meeting South Africa and Jamaica.
