The term 'bird-of-paradise' refers to a group of birds found in the tropical regions of New Guinea and Australia. These birds are known for their unique and colorful plumage, which is often used in courtship displays. The crossword solution for this term is 'OSCINE, ' which is a type of passerine bird, or perching bird. Oscines are distinguished by their vocal abilities, which are more complex than those of other passerines.