The correct spelling of the phrase "have to dinner" is "have dinner". The phonetic transcription of this phrase in IPA is /hæv ˈdɪnər/. The word "to" is unnecessary and incorrect in this context. The correct usage of "have to" signifies an obligation or necessity, for example, "I have to go to work". However, when referring to a meal, the correct phrase is simply "have dinner". It is important to use proper spelling and grammar to effectively communicate ideas.