The meaning of Parry Gripp's song "Hap, Hap, Hap, Happy Birthday" is quite simple and straightforward. The song celebrates someone's birthday and sends them good wishes for another year. The lyrics express happiness and cheerfulness for the occasion. The repetition of "Hap, hap, hap Happy Birthday" creates a catchy and joyful rhythm, emphasizing the happiness associated with birthdays. The line "We'll sing our cheers for another year" implies the celebration and appreciation of the person's existence and the hope for a prosperous future. However, the line "You live in a zoo, a zoo, a zoo, a zoo" might seem a bit peculiar or nonsensical. It is possible that this phrase is meant to be humorous or lighthearted, without a particular deeper meaning. It could be interpreted as a playful way of saying that the birthday person's life is filled with excitement and liveliness, like being in a zoo. Overall, the song aims to spread joy and happiness on someone's special day and to create a festive and upbeat atmosphere.