The word "鸵鸟" is formed by combining the character "鸵", which specifically denotes the ostrich, with the character "鸟", meaning bird, to create a compound term that literally means "ostrich bird". The character "鸵" itself is constructed with the "鸟" radical on the right to indicate its avian category, while the left component "它" historically provided a phonetic clue. Thus, the word directly specifies the ostrich through both semantic categorization and phonetic association.