The 'Candy' hitmaker - who recently became a father for the first time when wife Ayda Field gave birth to their daughter Theodora 'Teddy' Rose - was left red-faced by the blunder but blames the actress and her husband Chris Martin for giving the little girl such a ''stupid'' moniker.
He said: ''Recently the two of them were over at my house for a party. Gwyneth came over to me with her kiddo and I asked, 'Does little melon like an Apple?' So embarrassing! I mixed it up! But that happens if you have a stupid name like that. You should save your child from that.''
Although some people might consider Theodora an unusual name, Robbie insists people should stick to choosing normal names for their children.
He added to the German edition of GQ magazine: ''If you don't call your child Michael or Peter or Julia there will only be celebrity names left and they are all stupid.''
And the 38-year-old singer - who recently returned to the UK after living in Los Angeles - admitted the only TV he watches are reality shows because he thinks actors are ''a**holes''.
He said: ''I never watch shows in which actors appear. Only reality shows. I lived in Hollywood for 10 years surrounded by actors and I can tell you, They're all real a**holes.''